TWO-DIMENSIONAL (2D) NANOCOMPOSITE, PREPARATION METHOD, AND USE THEREOF

Abstract

A nanocomposite includes an oxygen vacancy-containing BiOX particle and a coating, where the coating is a biocompatible material. Under near-infrared (NIR) irradiation, the nanocomposite has a photothermal conversion efficiency of greater than or equal to 10%. Under NIR irradiation, the nanocomposite degrades 1,3-diphenylisobenzofuran (DPBF) at a rate of higher than or equal to 0.1 mmol/h. BiOX may be BiOF, BiOCl, BiOBr, BiOI, or BiOAt. A preparation method and a use of the nanocomposite are further provided. The nanocomposite is a bismuth oxyhalide nanomaterial with different numbers of oxygen vacancies and can be used for the photothermal therapy (PTT) of a tumor and for the integrated tumor diagnosis and treatment. The nanocomposite leads to an excellent therapeutic effect under the guidance of multi-modality imaging, and has excellent computed tomography (CT) imaging and photoacoustic imaging (PAI) performance.

Claims

1. A nanocomposite, comprising an oxygen vacancy-containing BiOX particle and a coating, wherein the coating is a biocompatible material; under a near-infrared (NIR) irradiation, the nanocomposite has a photothermal conversion efficiency of greater than or equal to 10%; under the NIR irradiation, the nanocomposite degrades 1,3-diphenylisobenzofuran (DPBF) at a rate of higher than or equal to 0.1 mmol/h; and BiOX is at least one selected from the group consisting of BiOF, BiOCl, BiOBr, BiOI, and BiOAt.

2. The nanocomposite according to claim 1, wherein a proportion of an oxygen vacancy in the oxygen vacancy-containing BiOX particle is 20% or higher; preferably, the proportion of the oxygen vacancy in the oxygen vacancy-containing BiOX particle is 20% to 30%; preferably, the proportion of the oxygen vacancy in the oxygen vacancy-containing BiOX particle is 40% or higher; preferably, under an NIR-II irradiation, the nanocomposite has the photothermal conversion efficiency of greater than or equal to 10%; preferably, under the NIR-II irradiation, the nanocomposite has the photothermal conversion efficiency of greater than or equal to 40%; preferably, under the NIR-II irradiation, the nanocomposite degrades the DPBF at the rate of higher than or equal to 1 mmol/h; preferably, the nanocomposite has a computed tomography (CT) signal grey value of greater than or equal to 100; preferably, the nanocomposite has a photoacoustic imaging (PAI) signal value of greater than or equal to 100.

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10. The nanocomposite according to claim 1, wherein the oxygen vacancy-containing BiOX particle has a particle size of greater than or equal to 0.1 nm; preferably, the oxygen vacancy-containing BiOX particle has the particle size of 0.1 nm to 500 nm.

11. (canceled)

12. The nanocomposite according to claim 1, wherein when BiOX is BiOCl, BiOCl particles with different numbers of oxygen vacancies are two-dimensional (2D) layered crystals.

13. The nanocomposite according to claim 1, wherein the coating is at least one selected from the group consisting of a siloxane polymer, a polysaccharide, a derivative of the polysaccharide, an amino acid, a derivative of the amino acid, a polyol, a derivative of the polyol, a polymer polyol, polyacrylic acid (PAA), and a derivative of the PAA.

14. The nanocomposite according to claim 13, wherein the coating is at least one selected from the group consisting of polyethylene glycol (PEG), a derivative of the PEG, mannitol, modified chitosan, dextran, carboxyl dextran, liposome, albumin, tetraethylorthosilicate (TEOS), the PAA, meglumine, arginine, polyglutamic acid (PGA), and polypeptide.

15. The nanocomposite according to claim 1, wherein a mass ratio of the oxygen vacancy-containing BiOX particle to the coating is 100:1 to 1:1.

16. A preparation method of the nanocomposite according to claim 1, comprising the following steps: a) acquiring the oxygen vacancy-containing BiOX particle; and b) coating the oxygen vacancy-containing BiOX particle to obtain the nanocomposite.

17. The preparation method of the nanocomposite according to claim 16, comprising the following steps: a1) thoroughly mixing a Bi-containing oxycompound, a Bi-containing halide, and a solvent, and allowing a solvothermal reaction to produce a first oxygen vacancy-containing BiOX particle, wherein a proportion of an oxygen vacancy in the first oxygen vacancy-containing BiOX particle is 20% to 30%; and b) mixing a first dispersion of the first oxygen vacancy-containing BiOX particle with a coating-containing solution or a coating precursor-containing solution, and allowing a reaction to produce the nanocomposite.

18. The preparation method of the nanocomposite according to claim 16, comprising the following steps: a1) thoroughly mixing a Bi-containing oxycompound, a Bi-containing halide, and a solvent, and allowing a solvothermal reaction to produce a first oxygen vacancy-containing BiOX particle, wherein a proportion of an oxygen vacancy in the first oxygen vacancy-containing BiOX particle is 20% to 30%; a2) subjecting a first dispersion of the first oxygen vacancy-containing BiOX particle to a reduction treatment to produce a second dispersion of a second oxygen vacancy-containing BiOX particle, wherein a proportion of an oxygen vacancy in the second oxygen vacancy-containing BiOX particle is 40% or higher; and b) mixing the second dispersion with a coating-containing solution or a coating precursor-containing solution, and allowing a reaction to obtain the nanocomposite.

19. The preparation method of the nanocomposite according to claim 17, wherein in step a1), a mass ratio of the Bi-containing oxycompound to the Bi-containing halide is (10-1):(0.1-1).

20. The preparation method of the nanocomposite according to claim 17, wherein in step a1), the Bi-containing oxycompound is at least one selected from the group consisting of Bi.sub.2O.sub.3, Bi.sub.2(SO.sub.4).sub.3, Bi(NO.sub.3).sub.3.5H.sub.2O, BiPO.sub.4, BiH(PO.sub.3).sub.2, BiH.sub.2PO.sub.3, Bi.sub.2(CO.sub.3).sub.3, Bi.sub.2(SO.sub.4).sub.3, and BiFeO.sub.3; the Bi-containing halide is at least one selected from the group consisting of BiF.sub.3, BiCl.sub.3, BiBr.sub.3, BiI.sub.3, and BiAt.sub.3; and the solvent is at least one selected from the group consisting of methanol, formaldehyde, ethanol, acetaldehyde, ethylene glycol (EG), diethylene glycol (DEG), dimethylformamide (DMF), benzyl alcohol, hydrazine hydrate, sodium borohydride (SBH), hydroiodic acid, acetone, dichloromethane (DCM), and trichloromethane (TCM).

21. The preparation method of the nanocomposite according to claim 17, wherein in step a1), the solvothermal reaction is conducted at 80° C. to 180° C. for 6 h to 48 h.

22. The preparation method of the nanocomposite according to claim 18, wherein in step a2), the reduction treatment comprises an ultraviolet (UV) light treatment or a reducing agent treatment.

23. The preparation method of the nanocomposite according to claim 22, wherein the UV light treatment is conducted at 10 W to 500 W for 2 h to 12 h.

24. The preparation method of the nanocomposite according to claim 22, wherein the reducing agent treatment comprises calcining the first dispersion of the first oxygen vacancy-containing BiOX particle in the presence of a reducing agent at 300° C. to 400° C. for 2 h to 12 h.

25. The preparation method of the nanocomposite according to claim 24, wherein the reducing agent is at least one selected from the group consisting of SBH, potassium borohydride (KBH), stannous chloride, oxalic acid, and dithizone.

26. The preparation method of the nanocomposite according to claim 24, wherein a mass ratio of the reducing agent to the first oxygen vacancy-containing BiOX particle is 1:(100-1).

27. The preparation method of the nanocomposite according to claim 17, wherein in step b), the reaction is conducted at 20° C. to 35° C. under stirring.

28. The nanocomposite according to claim 1, wherein the nanocomposite is used in at least one of the following: a preparation of a nanomaterial for photothermal therapy (PTT) of a tumor, a preparation of a nanomaterial for photodynamic therapy (PDT) of the tumor, a preparation of a tumor-targeted drug, a preparation of a material for tumor diagnosis, a preparation of a material for tumor diagnosis in vitro and in vivo, a cell isolation, a drug carrier, a preparation of a material for heavy-ion therapy, a preparation of a material for isotope diagnosis and treatment, and a preparation of a material for integrated tumor diagnosis and treatment.

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Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0093] FIG. 1 is a schematic diagram of a main preparation process of Example 1.

[0094] FIGS. 2A-2C show the transmission electron microscopy (TEM) images of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1, where FIG. 2A shows a white bismuth oxyhalide material without oxygen vacancies corresponding to sample 1-1; FIG. 2B shows a grey bismuth oxyhalide material with a small number of oxygen vacancies corresponding to sample 1-2; and FIG. 2C shows a black bismuth oxyhalide nanomaterial with a large number of oxygen vacancies corresponding to sample 1-3.

[0095] FIGS. 3A-3F show the theoretical calculation results of crystal structures of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1, where FIG. 3A shows a {001} crystal plane with no oxygen vacancies; FIG. 3B shows a {001} crystal plane with a small number of oxygen vacancies; FIG. 3C shows a {001} crystal plane with a large number of oxygen vacancies; FIG. 3D shows a {100} crystal plane with no oxygen vacancies; FIG. 3E shows a {100} crystal plane with a small number of oxygen vacancies; and FIG. 3F shows a {100} crystal plane with a large number of oxygen vacancies.

[0096] FIG. 4 shows the electron spin resonance (ESR)/electron paramagnetic resonance (EPR) test results of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1.

[0097] FIGS. 5A-5B show the photothermal heating curves of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1, where FIG. 5A shows the photothermal heating curves of the bismuth oxyhalide nanomaterial with a small number of oxygen vacancies and FIG. 5B shows the photothermal heating curves of the bismuth oxyhalide nanomaterial with a large number of oxygen vacancies.

[0098] FIGS. 6A-6B show the DPBF degradation rate test results of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1, where FIG. 6A shows the DPBF degradation rates of the bismuth oxyhalide nanomaterial with a small number of oxygen vacancies and FIG. 6B shows the DPBF degradation rates of the bismuth oxyhalide nanomaterial with a large number of oxygen vacancies.

[0099] FIG. 7 shows the comparison of in vivo CT imaging of the 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies obtained in Example 1.

[0100] FIGS. 8A-8B show the X-ray photoelectron spectroscopy (XPS) test results of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1, where FIG. 8A shows XPS spectra of sample 1-2 and FIG. 8B shows XPS spectra of sample 1-3.

[0101] FIG. 9 shows the cytotoxicity test results of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1.

[0102] FIG. 10 shows the cell therapy test results of the 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies obtained in Example 1.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0103] The present disclosure will be described in detail below with reference to the examples, but the present disclosure is not limited to these examples.

[0104] Unless otherwise specified, the raw materials in the examples of the present disclosure are all purchased from commercial sources.

[0105] Terms

[0106] As used herein, the terms “2D nanoparticle”, “nanoparticle”, and “bismuth oxyhalide with an oxygen vacancy” can be used interchangeably, and all refer to a nanoparticle with the following characteristics:

[0107] 1) the 2D nanomaterial is an oxyhalide of bismuth;

[0108] 2) the 2D nanomaterial has a particle size of greater than or equal to 0.1 nm;

[0109] 3) the 2D nanomaterial has a photothermal conversion efficiency of greater than or equal to 10%; and

[0110] 4) the 2D bismuth oxyhalide nanomaterial with an oxygen vacancy has a CT signal intensity (grey value) of greater than or equal to 200 (SIEMENS SOMATOM Definition AS+).

[0111] As used herein, the terms “2D bismuth oxyhalide nanomaterial with an oxygen vacancy”, “nanocomposite”, and “composite nanoparticle” can be used interchangeably, and all refer to a composite obtained by coating an outer surface of a 2D nanomaterial with a nanosphere or macromolecule.

[0112] As used herein, the term “PEG” is an abbreviation for polyethylene glycol.

[0113] As used herein, the term “DEG” is an abbreviation for diethylene glycol.

[0114] As used herein, the term “PEI” is an abbreviation for polyetherimide.

[0115] As used herein, the term “PVP” is an abbreviation for polyvinylpyrrolidone.

[0116] As used herein, the term “PLGA” is an abbreviation for poly(lactic acid-glycolic acid) copolymer. As used herein, the term “CT” is an abbreviation for computed tomography.

[0117] As used herein, the term “PAI” is an abbreviation for photoacoustic imaging.

[0118] As used herein, the term “DPBF” is an abbreviation for 1,3-diphenylisobenzofuran.

[0119] As used herein, the term “room temperature” refers to 0° C. to 30° C. and preferably 4° C. to 25° C.

[0120] 2D Nanomaterials in the Present Disclosure

[0121] The BiOX (X=F, Cl, Br, I, or At) nanomaterials are excellent semiconductor photocatalysts. With special electronic structures, the BiOX nanomaterials have been reported to have a strong laser-induced ROS production ability, and Bi 6s and O 2p can form a prominent hybrid valence band. The hybridization of Bi 6s and O 2p makes the valence band dispersed to a large extent, which is conducive to the migration of light-induced holes in the valence band and the progress of an oxidation reaction. Therefore, ultrathin nanosheets of such nanomaterials have received more and more attention in energy conversion and storage. Such an ultrathin nanosheet with a 2D structure makes photoexcited EHPs reach a surface more easily than EHPs generated in vivo, which reduces the recombination chance. The atomic thickness and surface distortion and defect of an ultrathin 2D crystal play an important role in the electronic structural modification and performance improvement of the crystal.

[0122] However, most of the BiOX nanomaterials have a wide band gap, can only be excited by high-energy UV light or X-rays, and are only used in the radiotherapy of tumors, which inevitably causes damage to healthy tissues. Moreover, due to the wide band gap, BiOX nanomaterials do not possess photothermal properties. Inspired by the above analysis, the present disclosure proposes an ultrathin BiOX nanosheet with a large number of surface/subsurface defects, which introduces the photothermal properties while retaining the photoexcited ROS production ability to enable the efficient diagnosis and treatment of tumors.

[0123] In the present disclosure, a surface of the 2D nanomaterial is coated with a polymer microsphere to significantly enhance the biocompatibility of the 2D nanomaterial and reduce the toxicity of the nanomaterial (especially when it is used at a high dosage).

[0124] General Test Methods

[0125] TEM

[0126] Test instrument: JEOL-2100 transmission electron microscope; test conditions: 200 Kv and 101 μA; and nanoparticles to be tested are first dispersed in water and then tested.

[0127] CT Value Measurement

[0128] Test instrument: SIEMENS SOMATOM Definition AS+; and test conditions may include tube voltage of 80 kV and tube current of 150 mAs.

[0129] Small Animal CT Imaging

[0130] Test instrument: SIEMENS SOMATOM Definition AS+; and test conditions may include tube voltage of 80 kV, 100 kv, and 120 kv and tube current of 150 mAs.

[0131] DPBF Degradation Experiment

[0132] 10 mL of an ethanol solution with DPBF at a concentration of 50 mg/mL is mixed with a 100 μg/mL oxygen vacancy-containing bismuth oxychloride material solution. The resulting mixture is irradiated for 1 h at a laser power density of 50 mW cm.sup.−2. 1 mL of a sample is taken at different time points. The absorbance of a supernatant of the sample at 400 nm is determined by ultraviolet-visible (UV-Vis) spectrophotometry.

[0133] Cytotoxicity Test

[0134] 1. 4T1 cells are prepared into a suspension with a concentration of 1*10{circumflex over ( )}6/mL. 100 μL of the suspension is taken and dispersed in 100 μL of a medium composed of 95 v/v % 1640 medium and 5 v/v % fetal bovine serum (FBS). The resulting dispersion is added to a 96-well plate and incubated overnight.

[0135] 2. The medium is removed, then 100 μL of each of the nanocomposites in Example 1 is added to each well at different concentrations of 100 m/mL, 200 m/mL, 300 m/mL, 400 μg/mL, and 500 m/mL, and the cells are further incubated for 24 h.

[0136] 3. 20 h later, the nanocomposites are each taken out, the plate is washed 2 to 3 times with phosphate buffered saline (PBS), then 100 μL of the above medium and 5% methyl thiazolyl tetrazolium (MTT) (dissolved in dimethyl sulfoxide (DMSO)) are added, and then the cells are further incubated for 4 h.

[0137] 4. The liquid in each well is removed, 100 μL of DMSO is added, the absorbance of each well of the 96-well plate at 550 nm is determined by a microplate reader, and a cell viability is calculated.

[0138] Cell Therapy Test

[0139] 1. 4T1 cells are prepared into a suspension with a concentration of 1*10{circumflex over ( )}6/mL. 100 μL of the suspension is taken and dispersed in 100 μL of a medium composed of 95 v/v % 1640 medium and 5 v/v % FBS. The resulting dispersion is added to a 96-well plate and incubated overnight.

[0140] 2. The medium is removed, then 100 μL of each of the nanocomposites in Example 1 is added to each well at different concentrations of 100m/mL, 200m/mL, 300m/mL, 400 μg/mL, and 500m/mL, and the cells are further incubated for 4 h.

[0141] 3. 4 h later, the nanocomposites are each taken out, the plate is washed 2 to 3 times with PBS, and then 100 μL of the above medium is added.

[0142] 4. Each well of the 96-well plate is irradiated with an 808 nm laser at a laser power density of 1.0 W/cm.sup.2.

[0143] 5. After the irradiation, the cells are further incubated for 20 h. Then 5% MTT (dissolved in DMSO) is added, and the cells are further incubated for 4 h.

[0144] 6. The liquid in each well is removed, 100 μL of DMSO is added, the absorbance of each well of the 96-well plate at 550 nm is determined by a microplate reader, and a cell viability is calculated.

Example 1

[0145] Preparation of a White Bismuth Oxyhalide Material without Oxygen Vacancies

[0146] (1-1-1) 486 mg of Bi(NO.sub.3).sub.3.5H.sub.2O, 400 mg of PVP, and 455 mg of mannitol were weighed, mixed, and dissolved in 25 mL of ultrapure water (UPW), and a resulting mixed solution was stirred for 10 min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution a;

[0147] (1-1-2) Under continuous stirring, 5 mL of a saturated NaCl solution was slowly added dropwise to the solution a through a syringe to obtain a white homogeneous suspension b;

[0148] (1-1-3) The white homogeneous suspension b was subjected to ultrasonic dispersion for 10 min and then transferred to a 50 ml polytetrafluoroethylene (PTFE) hydrothermal reactor to undergo a hydrothermal reaction at 160° C. for 3 h. A resulting reaction solution was cooled. A resulting precipitate was separated, washed 8 times alternately with water and ethanol, and then dried to obtain the white bismuth oxyhalide material c for later use, which was denoted as sample 1-1.

[0149] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0150] (1-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min by an ultrasonic machine to obtain a solution d.

[0151] (1-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 12 h; and

[0152] after the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol, and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 1-2.

[0153] (1-2-3) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0154] (1-2-4) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 1-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0155] (1-2-5) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (1-2-4), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 1-4 and stored at 4° C.

[0156] Results

[0157] The 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1 were each subjected to TEM, ESR/EPR, and photothermal heating tests (for material characterization), cytotoxicity and cell therapy tests, animal therapy and animal tissue section tests (for in vivo toxicity analysis), and CT value measurement and CT imaging performance tests.

[0158] FIG. 1 shows a preparation process and technical route of the material.

[0159] It can be known from FIG. 1 that core technologies of the present disclosure are mainly as follows: a hydrothermal reaction is used to synthesize a defect-free 2D bismuth oxyhalide material; a solvothermal reaction is used to synthesize a 2D bismuth oxyhalide material with a small number of oxygen vacancies; and the UV light reduction is used to produce more oxygen vacancies to reduce a band gap of the material, such that the material can achieve full-spectrum absorption and can achieve PTT and PDT simultaneously under NIR irradiation. The bismuth element enables CT/PAI dual-modality imaging, and thus the bismuth oxyhalide material can achieve the combined photothermal and photodynamic therapy of a tumor under the accurate guidance of dual-modality imaging.

[0160] FIGS. 2A-2C show the TEM images of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1, where FIG. 2A shows a white bismuth oxyhalide material without oxygen vacancies corresponding to sample 1-1; FIG. 2B shows a grey bismuth oxyhalide material with a small number of oxygen vacancies corresponding to sample 1-2; and FIG. 2C shows a black bismuth oxyhalide nanomaterial with a large number of oxygen vacancies corresponding to sample 1-3. It can be seen from FIGS. 2A-2C that the synthesized materials are BiOCl materials.

[0161] It can be known from FIGS. 2A-2C that the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies have an average particle size of about 100 nm, and lattice fringes are obvious in the high-resolution TEM images.

[0162] FIGS. 3A-3F show the theoretical calculation results of crystal structures of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1, where FIG. 3A shows a {001} crystal plane with no oxygen vacancies; FIG. 3B shows a {001} crystal plane with a small number of oxygen vacancies; FIG. 3C shows a {001} crystal plane with a large number of oxygen vacancies; FIG. 3D shows a {100} crystal plane with no oxygen vacancies; FIG. 3E shows a {100} crystal plane with a small number of oxygen vacancies; and FIG. 3F shows a {100} crystal plane with a large number of oxygen vacancies.

[0163] It can be seen from FIGS. 3A-3F that, among the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies, the crystal structure constantly varies with the increase of oxygen vacancies.

[0164] FIG. 4 shows the ESR/EPR test results of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1, where defect-free BiOX corresponds to sample 1-1, BiOX with a small number of defects corresponds to sample 1-2, and BiOX with a large number of defects corresponds to sample 1-3.

[0165] It can be seen from FIG. 4 that, among the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies, the oxygen vacancy peak in the ESR test result constantly increases with the increase of oxygen vacancies.

[0166] The 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies prepared in Example 1 were each subjected to an XPS test using an instrument of Axis Ultra DLD X-ray photoelectron spectrometer. The conventional XPS qualitative, semi-quantitative, valence band, and chemical valence analysis were conducted with an analysis element of oxygen (O).

[0167] FIGS. 8A-8B show the XPS test results of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1, where FIG. 8A shows XPS spectra of sample 1-2 and FIG. 8B shows XPS spectra of sample 1-3. In FIGS. 8A-8B, “CPS” represents a synthesis peak, “abs” represents adsorbed oxygen, “O—H” represents an oxygen vacancy, and “O—Bi” represents a bismuth-oxygen bond. It can be seen from (a) in FIGS. 8A-8B that a proportion of oxygen vacancies in sample 1-2 is 30%. It can be seen from (b) in FIGS. 8A-8B that a proportion of oxygen vacancies in sample 1-3 is about 50%.

[0168] The 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies prepared in Example 1 were each subjected to a photothermal test, and a test process was as follows: the materials (dispersed in water) were each placed in a cuvette at different concentrations (100 μg/mL, 200 μg/mL, 300 μg/mL, 400 μg/mL, and 500 μg/mL) and then irradiated with a 1,060 nm NIR laser (at a power density of 1 W/cm.sup.2), and the temperature changes of the materials were measured with a thermal imager.

[0169] FIGS. 5A-5B show the photothermal heating data of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1, where FIG. 5A shows the photothermal heating curves of the 2D bismuth oxyhalide nanomaterial with a small number of oxygen vacancies (sample 1-2) and FIG. 5B shows the photothermal heating curves of the 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies (sample 1-3).

[0170] It can be seen from FIG. 5A that the 2D bismuth oxyhalide nanomaterial with a small number of oxygen vacancies exhibits a poor photothermal heating effect under 1,060 nm laser; and it can be seen from FIG. 5B that the 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies exhibits a prominent photothermal heating effect under 1,060 nm laser and has a high photothermal conversion efficiency.

[0171] FIGS. 6A-6B show the in vitro DPBF degradation test data of the bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1, where FIG. 6A shows the DPBF degradation test data of the 2D bismuth oxyhalide nanomaterial with a small number of oxygen vacancies (sample 1-2) and FIG. 6B shows the DPBF degradation test data of the 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies (sample 1-3).

[0172] It can be seen from FIGS. 6A-6B that the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies all exhibit a strong ROS production ability.

[0173] The 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies prepared in Example 1 were each subjected to a CT imaging test, and a test process was as follows: the bismuth oxyhalide materials in different concentrations and the CT contrast agent iopamidol used clinically were each dispersed in 5% agar at the same molar concentration, fixed, and tested by SIEMENS SOMATOM Definition AS for CT value and CT imaging under a tube voltage of 80 kV and tube current of 150 mAs.

[0174] FIG. 7 shows the in vivo CT imaging results of the 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies obtained in Example 1. The right panel shows the CT imaging of the bismuth oxyhalide material with a large number of oxygen vacancies in a mouse injected with the bismuth oxyhalide material through the tail vein. The left panel shows the CT imaging of a control group injected with the same amount of an injection without the bismuth oxyhalide material. A test process was as follows: The mouse was injected with 100 μL of an aqueous solution of sample 1-3 (the bismuth oxyhalide nanomaterial with a large number of oxygen vacancies) at a concentration of 3 mg/mL, and 6 h later, the CT imaging test was conducted. The imaging result of the experimental group is shown in the right panel of FIG. 7, and the imaging result of the control group is shown in the left panel of FIG. 7.

[0175] It can be seen from FIG. 7 that the 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies obtained in Example 1 has a strong signal intensity, and can be enriched in a tumor area through the EPR effect after a period of time, indicating that the 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies obtained in Example 1 is a prominent CT imaging material.

[0176] The 2D bismuth oxyhalide nanomaterials with different numbers of oxygen vacancies prepared in Example 1 were each subjected to a cytotoxicity test, and test results are shown in FIG. 9. In FIG. 9, “no oxygen vacancies” corresponds to sample 1-1, a nanocomposite prepared according to steps (1-2-3) and (1-2-4); “a small number of oxygen vacancies” corresponds to sample 1-2, a nanocomposite prepared according to steps (1-2-3) and (1-2-4); and “a large number of oxygen vacancies” corresponds to sample 1-4. The test results show that, in the presence of the different nanocomposites at different concentrations, a cell viability is nearly 100%, indicating that the nanocomposites have little toxicity to cells.

[0177] The 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies (sample 1-4) prepared in Example 1 was subjected to a cell therapy test, and test results are shown in FIG. 10. The test results show that, under IR irradiation at different powers, different concentrations of the nanocomposite lead to a prominent killing effect on cancer cells, and nearly 50% of the cancer cells are killed.

Example 2

[0178] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0179] (2-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0180] (2-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 160° C. for 12 h; and

[0181] after the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol, and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 2-2.

[0182] (2-2-3) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0183] (2-2-4) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 2-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0184] (2-2-5) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (2-2-4). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 2-4, and stored at 4° C.

[0185] Results

[0186] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 2 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 3

[0187] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0188] (3-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0189] (3-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 140° C. for 12 h; and

[0190] after the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol, and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 3-2.

[0191] (3-2-3) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0192] (3-2-4) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 3-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0193] (3-2-5) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (3-2-4). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 3-4, and stored at 4° C.

[0194] Results

[0195] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 3 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 4

[0196] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0197] (4-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0198] (4-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 140° C. for 12 h; and

[0199] after the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol, and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 4-2.

[0200] (4-2-3) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 300 W mercury lamp for 4 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0201] (4-2-4) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 4-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0202] (4-2-5) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (4-2-4). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 4-4, and stored at 4° C.

[0203] Results

[0204] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 4 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 5

[0205] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0206] (5-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0207] (5-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 6 h; and

[0208] after the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol, and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 5-2.

[0209] (5-2-3) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 300 W mercury lamp for 4 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0210] (5-2-4) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 5-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0211] (5-2-5) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5-2-4). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 5-4, and stored at 4° C.

[0212] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 5 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 6

[0213] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0214] (6-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0215] (6-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 6 h; and

[0216] after the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol, and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 5-2.

[0217] (6-2-3) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 300 W mercury lamp for 4 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0218] (6-2-4) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 6-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0219] (6-2-5) 10 mL of a solution of PEG in ethanol (with a concentration of 25 mg/mL) was added to the dispersion obtained in step (6-2-4). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 6-4 and stored at 4° C.

[0220] Results

[0221] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 6 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 7

[0222] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0223] (7-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0224] (7-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 6 h; and

[0225] after the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol, and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 7-2.

[0226] (7-2-3) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and mixed with 2 g of dithizone. A resulting powdery mixture was transferred to a tube furnace and calcined at 400° C. for 2 h to obtain a bismuth oxyhalide nanomaterial d with a large number of oxygen vacancies.

[0227] (7-2-4) The bismuth oxyhalide nanomaterial d was washed 8 times with water and ethanol to obtain a solid, which was denoted as sample 7-3; the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0228] (7-2-5) 10 mL of a solution of PEG in ethanol (with a concentration of 25 mg/mL) was added to the dispersion obtained in step (7-2-4). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 7-4, and stored at 4° C.

[0229] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 7 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 8

[0230] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0231] (8-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min by an ultrasonic machine to obtain a solution d.

[0232] (8-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 6 h; and

[0233] after the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol, and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 8-2.

[0234] (8-2-3) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0235] (8-2-4) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 8 times with water and ethanol to obtain a solid, which was denoted as sample 8-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0236] (8-2-5) 10 mL of a solution of PEI in DMF (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (8-2-4). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 8-4, and stored at 4° C.

[0237] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 8 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 9

[0238] (9-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0239] (9-2-2) The solution a was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 6 h.

[0240] (9-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, and a resulting supernatant was removed. A resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use.

[0241] (9-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0242] (9-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0243] (9-2-6) 10 mL of a solution of PVP in acetone (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was stored at 4° C.

[0244] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 9 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 10

[0245] (10-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG, and a resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0246] (10-2-2) The solution a was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 6 h.

[0247] (10-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, and a resulting supernatant was removed. A resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use.

[0248] (10-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0249] (10-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min, a resulting precipitate was washed 4 times with water and ethanol to obtain a solid, and the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0250] (10-2-6) 50 mL of a solution of PLGA in water was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was stored at 4° C.

[0251] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 10 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 11

[0252] (11-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0253] (11-2-2) The solution a was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 6 h.

[0254] (11-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, and a resulting supernatant was removed. A resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use.

[0255] (11-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0256] (11-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, and the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0257] (11-2-6) 10 mL of a solution of arginine in EG (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was stored at 4° C.

[0258] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 11 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 12

[0259] (12-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiF.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0260] (12-2-2) The solution a was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 6 h.

[0261] (12-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, and a resulting supernatant was removed. A resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use.

[0262] (12-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0263] (12-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, and the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0264] (12-2-6) 10 mL of a solution of arginine in EG (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was stored at 4° C.

[0265] Results

[0266] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 12 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 13

[0267] (13-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiAt.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0268] (13-2-2) The solution a was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 6 h.

[0269] (13-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature. A resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use.

[0270] (13-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0271] (13-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, and the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0272] (13-2-6) 10 mL of a solution of arginine in EG (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was stored at 4° C.

[0273] Results

[0274] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 13 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 14

[0275] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0276] (14-2-1) 0.71 g of Bi.sub.2(SO.sub.4).sub.3 and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min using an ultrasonic machine to obtain a solution d.

[0277] (14-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 160° C. for 12 h.

[0278] (14-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature. A resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol, and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 14-2.

[0279] (14-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0280] (14-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 14-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0281] (14-2-6) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 14-4 and stored at 4° C.

[0282] Results

[0283] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 14 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 15

[0284] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0285] (15-2-1) 0.47 g of Bi.sub.2O.sub.3 and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0286] (15-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 160° C. for 12 h.

[0287] (15-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, and a resulting supernatant was removed. A resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 15-2.

[0288] (15-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0289] (15-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 15-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0290] (15-2-6) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 15-4, and stored at 4° C.

[0291] Results

[0292] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 15 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 16

[0293] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0294] (16-2-1) 0.61 g of BiPO.sub.4 and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0295] (16-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 160° C. for 12 h.

[0296] (16-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, and a resulting supernatant was removed. A resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 16-2.

[0297] (16-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0298] (16-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 16-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0299] (16-2-6) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 16-4 and stored at 4° C.

[0300] Results

[0301] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 16 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 17

[0302] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0303] (17-2-1) 1.41 g of (BiO).sub.2CO.sub.3.½H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0304] (17-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 160° C. for 12 h.

[0305] (17-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, and a resulting supernatant was removed. A resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 17-2.

[0306] (17-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0307] (17-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 17-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0308] (17-2-6) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 17-4 and stored at 4° C.

[0309] Results

[0310] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 17 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 18

[0311] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0312] (18-2-1) 0.62 g of BiFeO.sub.3.½H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0313] (18-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 160° C. for 12 h.

[0314] (18-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, and a resulting supernatant was removed. A resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 18-2.

[0315] (18-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0316] (18-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 18-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0317] (18-2-6) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 18-4, and stored at 4° C.

[0318] Results

[0319] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 18 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 19

[0320] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0321] (19-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.266 g of BiF.sub.3 were weighed and dissolved in 40 mL of DEG, and a resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0322] (19-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 160° C. for 12 h.

[0323] (19-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, and a resulting supernatant was removed. A resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 19-2.

[0324] (19-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0325] (19-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 19-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0326] (19-2-6) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 19-4, and stored at 4° C.

[0327] Results

[0328] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 19 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 20

[0329] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0330] (20-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.449 g of BiBr.sub.3 were weighed and dissolved in 40 mL of DEG. A resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0331] (20-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 160° C. for 12 h.

[0332] (20-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, and a resulting supernatant was removed. A resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 20-2.

[0333] (20-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution. A resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0334] (20-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 20-3. The solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0335] (20-2-6) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5). A resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min. A resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 20-4, and stored at 4° C.

[0336] Results

[0337] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 20 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 21

[0338] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0339] (21-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.59 g of BiI.sub.3 were weighed and dissolved in 40 mL of DEG, and a resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0340] (21-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 160° C. for 12 h.

[0341] (21-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 21-2.

[0342] (21-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution, and a resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0343] (21-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 21-3; the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0344] (21-2-6) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 21-4, and stored at 4° C.

[0345] Results

[0346] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 21 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 22

[0347] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0348] (22-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.83 g of BiAt.sub.3 were weighed and dissolved in 40 mL of DEG, and a resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0349] (22-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 160° C. for 12 h.

[0350] (22-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 21-2.

[0351] (22-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and dispersed in 10 mL of an aqueous solution, and a resulting dispersion was transferred to a photochemical reactor and irradiated under a 500 W mercury lamp for 2 h to obtain a black bismuth oxyhalide nanomaterial-dispersed system f.

[0352] (22-2-5) The black bismuth oxyhalide nanomaterial-dispersed system f was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a solid, which was denoted as sample 22-3; the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0353] (22-2-6) 10 mL of a solution of PEG in ethanol (with a concentration of 50 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 22-4 and stored at 4° C.

[0354] Results

[0355] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 22 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 23

[0356] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0357] (23-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.59 g of BiI.sub.3 were weighed and dissolved in 40 mL of DEG, and a resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0358] (23-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 120° C. for 6 h.

[0359] (23-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 7-2.

[0360] (23-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and mixed with 2 g of dithizone, and a resulting powdery mixture was transferred to a tube furnace and calcined at 400° C. for 2 h to obtain a bismuth oxyhalide nanomaterial d with a large number of oxygen vacancies.

[0361] (23-2-5) The bismuth oxyhalide nanomaterial d was washed 8 times with water and ethanol to obtain a solid, which was denoted as sample 23-3; the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0362] (23-2-6) 10 mL of a solution of PLGA in ethanol (with a concentration of 25 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 23-4, and stored at 4° C.

[0363] Results

[0364] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 23 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 24

[0365] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0366] (24-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG, and a resulting mixed solution was continuously stirred for 20 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 20 min in an ultrasonic machine to obtain a solution d.

[0367] (24-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 6 h.

[0368] (24-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 24-2.

[0369] (24-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and mixed with 2 g of dithizone, and a resulting powdery mixture was transferred to a tube furnace and calcined at 400° C. for 4 h to obtain a bismuth oxyhalide nanomaterial d with a large number of oxygen vacancies.

[0370] (24-2-5) The bismuth oxyhalide nanomaterial d was washed 8 times with water and ethanol to obtain a solid, which was denoted as sample 24-3; the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0371] (24-2-6) 20 mL of a solution of arginine in ethanol (with a concentration of 25 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 160 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 24-4, and stored at 4° C.

[0372] Results

[0373] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 24 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 25

[0374] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0375] (25-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of ethanol, and a resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0376] (25-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 140° C. for 26 h.

[0377] (25-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 25-2.

[0378] (25-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and mixed with 2 g of dithizone, and a resulting powdery mixture was transferred to a tube furnace and calcined at 400° C. for 8 h to obtain a bismuth oxyhalide nanomaterial d with a large number of oxygen vacancies.

[0379] (25-2-5) The bismuth oxyhalide nanomaterial d was washed 8 times with water and ethanol to obtain a solid, which was denoted as sample 25-3; the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0380] (25-2-6) 10 mL of a solution of PVP in DEG (with a concentration of 25 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 25-4, and stored at 4° C.

[0381] Results

[0382] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 25 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 26

[0383] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0384] (26-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG, and a resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0385] (26-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 140° C. for 6 h.

[0386] (26-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 26-2.

[0387] (26-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and mixed with 2 g of SBH, and a resulting powdery mixture was transferred to a tube furnace and calcined at 400° C. for 2 h to obtain a bismuth oxyhalide nanomaterial d with a large number of oxygen vacancies.

[0388] (26-2-5) The bismuth oxyhalide nanomaterial d was washed 8 times with water and ethanol to obtain a solid, which was denoted as sample 26-3; the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0389] (26-2-6) 10 mL of a solution of PVP in ethanol (with a concentration of 25 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 26-4, and stored at 4° C.

[0390] Results

[0391] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 26 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 27

[0392] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0393] (27-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG, and a resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0394] (27-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 180° C. for 6 h.

[0395] (27-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 27-2.

[0396] (27-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and mixed with 2 g of SBH, and a resulting powdery mixture was transferred to a tube furnace and calcined at 400° C. for 2 h to obtain a bismuth oxyhalide nanomaterial d with a large number of oxygen vacancies.

[0397] (27-2-5) The bismuth oxyhalide nanomaterial d was washed 8 times with water and ethanol to obtain a solid, which was denoted as sample 27-3; the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0398] (27-2-6) 10 mL of a solution of PEG in ethanol (with a concentration of 25 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 27-4, and stored at 4° C.

[0399] Results

[0400] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 27 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 28

[0401] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0402] (28-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG, and a resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0403] (28-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 140° C. for 6 h.

[0404] (28-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 28-2.

[0405] (28-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and mixed with 4 g of SBH, and a resulting powdery mixture was transferred to a tube furnace and calcined at 400° C. for 2 h to obtain a bismuth oxyhalide nanomaterial d with a large number of oxygen vacancies.

[0406] (28-2-5) The bismuth oxyhalide nanomaterial d was washed 8 times with water and ethanol to obtain a solid, which was denoted as sample 28-3; the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0407] (28-2-6) 10 mL of a solution of PLGA in ethanol (with a concentration of 25 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 28-4 and stored at 4° C.

[0408] Results

[0409] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 28 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 29

[0410] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0411] (29-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG, and a resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0412] (29-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 140° C. for 6 h.

[0413] (29-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 29-2.

[0414] (29-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and mixed with 8 g of SBH, and a resulting powdery mixture was transferred to a tube furnace and calcined at 400° C. for 2 h to obtain a bismuth oxyhalide nanomaterial d with a large number of oxygen vacancies.

[0415] (29-2-5) The bismuth oxyhalide nanomaterial d was washed 8 times with water and ethanol to obtain a solid, which was denoted as sample 29-3; the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0416] (29-2-6) 10 mL of a solution of PLGA in ethanol (with a concentration of 25 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 29-4, and stored at 4° C.

[0417] Results

[0418] The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 29 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.

Example 30

[0419] Preparation of a Grey Bismuth Oxyhalide Material with a Small Number of Oxygen Vacancies and a Black Bismuth Oxyhalide Nanomaterial with a Large Number of Oxygen Vacancies

[0420] (30-2-1) 0.97 g of Bi(NO.sub.3).sub.3.5H.sub.2O and 0.315 g of BiCl.sub.3 were weighed and dissolved in 40 mL of DEG, and a resulting mixed solution was continuously stirred for 10 min on a magnetic stirrer at 80 r/min and then subjected to an ultrasonic treatment for 10 min in an ultrasonic machine to obtain a solution d.

[0421] (30-2-2) The solution d was transferred to a PTFE-lined hydrothermal reactor to undergo a reaction at 140° C. for 6 h.

[0422] (30-2-3) After the reaction was completed, a resulting reaction solution was cooled to room temperature, a resulting supernatant was removed, and a resulting precipitate was washed 4 times with water and ethanol and then dried to obtain a grey bismuth oxyhalide material e with a small number of oxygen vacancies for later use, which was denoted as sample 30-2.

[0423] (30-2-4) 50 mg of the grey bismuth oxyhalide material e with a small number of oxygen vacancies was taken and mixed with 8 g of SBH, and a resulting powdery mixture was transferred to a tube furnace and calcined at 400° C. for 4 h to obtain a bismuth oxyhalide nanomaterial d with a large number of oxygen vacancies.

[0424] (30-2-5) The bismuth oxyhalide nanomaterial d was washed 8 times with water and ethanol to obtain a solid, which was denoted as sample 30-3; the solid was dispersed in 10 mL of ethanol to obtain a dispersion.

[0425] (30-2-6) 10 mL of a solution of PVP in DEG (with a concentration of 25 mg/mL) was added to the dispersion obtained in step (5), and a resulting mixed solution was continuously stirred for 24 h on a magnetic stirrer at 80 r/min. After a reaction was completed, a resulting mixture was centrifuged at 10,000 r/min, and a resulting precipitate was washed 4 times with water and ethanol to obtain a black 2D bismuth oxyhalide nanomaterial with a large number of oxygen vacancies, which was denoted as sample 30-4, and stored at 4° C.

[0426] Results

The TEM, DPBF degradation rate, photothermal conversion efficiency, cytotoxicity, CT value measurement, and in vivo CT imaging test results of the 2D bismuth oxyhalide composites with different numbers of oxygen vacancies obtained in Example 30 are basically the same as those of Example 1. XPS shows that a proportion of oxygen vacancies in the grey bismuth oxyhalide nanomaterial is 20% to 40% and a proportion of oxygen vacancies in the black bismuth oxyhalide nanomaterial is greater than 40%.