NON-METALLIC HIGH-ENTROPY COMPOUND, AND PREPARATION METHOD AND USE THEREOF

Abstract

The present disclosure relates to the technical field of photocatalysis/electrocatalysis, and in particular to a non-metallic high-entropy compound, and a preparation method and use thereof. In the present disclosure, the non-metallic high-entropy compound includes at least five non-metallic elements, where each of the at least five non-metallic elements has a molar proportion of 0.1% to 99.0%, and a total atomic proportion of the at least five non-metallic elements are 100%. The non-metallic high-entropy compound has a controllable band gap, an adjustable conductivity, and a desirable surface activity, and shows a catalytic reaction activity for hydrogen production by high-efficiency photocatalytic/electrocatalytic water splitting, carbon dioxide reduction, or organic pollutant degradation. Moreover, synthetic raw materials are all non-metals, which are cheap and easily available, while a synthesis process is simple and easy to implement.

Claims

1. A non-metallic high-entropy compound, comprising at least five non-metallic elements, wherein each of the at least five non-metallic elements has a molar proportion of 0.1% to 99.0%, and a total atomic proportion of the at least five non-metallic elements are 100%.

2. The non-metallic high-entropy compound according to claim 1, wherein the non-metallic elements are selected from the group consisting of hydrogen, boron, carbon, nitrogen, oxygen, fluorine, phosphorus, sulfur, selenium, chlorine, bromine, iodine, and silicon.

3. A preparation method of the non-metallic high-entropy compound according to claim 1, comprising the following steps: S1, mixing at least five non-metallic element sources evenly to obtain a precursor solution; and S2, converting the precursor solution into the non-metallic high-entropy compound through solvothermal polymerization, vapor deposition, or electrochemical deposition.

4. The preparation method according to claim 3, wherein the non-metallic elements are selected from the group consisting of hydrogen, boron, carbon, nitrogen, oxygen, fluorine, phosphorus, sulfur, selenium, chlorine, bromine, iodine, and silicon.

5. The preparation method according to claim 3, wherein the non-metallic element source is one or a combination of two or more selected from the group consisting of an inorganic non-metallic acid, an inorganic non-metallic oxide, and a non-metallic organic substance.

6. The preparation method according to claim 4, wherein the non-metallic element source is one or a combination of two or more selected from the group consisting of an inorganic non-metallic acid, an inorganic non-metallic oxide, and a non-metallic organic substance.

7. The preparation method according to claim 3, wherein the non-metallic element source comprises but is not limited to boric acid, hydrogen iodide, diboron trioxide, cyanuric chloride, ethoxy(pentafluoro)cyclotriphosphazene, thioacetamide, methyl-hydroselenide, trimethylsilyl acetate, tri-tert-butyl borate, and carbamide.

8. The preparation method according to claim 4, wherein the non-metallic element source comprises but is not limited to boric acid, hydrogen iodide, diboron trioxide, cyanuric chloride, ethoxy(pentafluoro)cyclotriphosphazene, thioacetamide, methyl-hydroselenide, trimethylsilyl acetate, tri-tert-butyl borate, and carbamide.

9. The preparation method according to claim 3, wherein the mixing comprises but is not limited to mixing by dissolving, mixing by stirring, and mixing by grinding; and during the mixing by dissolving, the at least five non-metallic element sources are uniformly dispersed under stirring in a mixed solvent of ethanol and water at a volume ratio of 1:(0.5-1.5).

10. The preparation method according to claim 4, wherein the mixing comprises but is not limited to mixing by dissolving, mixing by stirring, and mixing by grinding; and during the mixing by dissolving, the at least five non-metallic element sources are uniformly dispersed under stirring in a mixed solvent of ethanol and water at a volume ratio of 1:(0.5-1.5).

11. The preparation method according to claim 3, wherein the solvothermal polymerization comprises one of a hydrothermal reaction and a calcination polymerization reaction; the hydrothermal reaction is conducted at 80? C. to 200? C. for 6 h to 36 h; and the calcination polymerization reaction is conducted at 500? C. to 700? C. for 1 h to 4 h.

12. The preparation method according to claim 4, wherein the solvothermal polymerization comprises one of a hydrothermal reaction and a calcination polymerization reaction; the hydrothermal reaction is conducted at 80? C. to 200? C. for 6 h to 36 h; and the calcination polymerization reaction is conducted at 500? C. to 700? C. for 1 h to 4 h.

13. The preparation method according to claim 3, wherein the vapor deposition specifically comprises: subjecting a vapor of the precursor solution to a reaction in a tubular furnace with an inert gas at a bubbling gas flow rate of 40 mL/min to 60 mL/min and a roasting temperature of 500? C. to 700? C. for 8 h to 12 h.

14. The preparation method according to claim 4, wherein the vapor deposition specifically comprises: subjecting a vapor of the precursor solution to a reaction in a tubular furnace with an inert gas at a bubbling gas flow rate of 40 mL/min to 60 ml/min and a roasting temperature of 500? C. to 700? C. for 8 h to 12 h.

15. The preparation method according to claim 3, wherein the electrochemical deposition specifically comprises: connecting an electrochemical workstation to the precursor solution to construct a three-electrode system, and conducting a reaction at a constant voltage of ?20 V for 8 h to 12 h.

16. The preparation method according to claim 4, wherein the electrochemical deposition specifically comprises: connecting an electrochemical workstation to the precursor solution to construct a three-electrode system, and conducting a reaction at a constant voltage of ?20 V for 8 h to 12 h.

17. A use method of the non-metallic high-entropy compound according to claim 1, comprising using the non-metallic high-entropy compound in hydrogen production by photocatalytic/electrocatalytic decomposition, carbon dioxide reduction, organic pollutant degradation, or an energy-storage electrode material.

18. The use method according to claim 17, wherein the non-metallic elements are selected from the group consisting of hydrogen, boron, carbon, nitrogen, oxygen, fluorine, phosphorus, sulfur, selenium, chlorine, bromine, iodine, and silicon.

Description

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] It should be noted that the following detailed descriptions are exemplary and are intended to provide further descriptions of the present disclosure. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0030] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit exemplary embodiments according to the present disclosure. As used herein, unless otherwise specified herein, the singular forms are also intended to include the plural forms. In addition, it should also be understood that when the terms comprise and/or include are used in this specification, they specify the presence of features, steps, operations, devices, components, and/or combinations thereof.

[0031] The technical solution in the present disclosure will be clearly and completely described below in conjunction with the examples of the present disclosure. Apparently, the described examples are a part of, but not all of, the examples of the present disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of the present disclosure without creative efforts shall fall within the protection scope of the present disclosure.

[0032] EXAMPLE 1

Non-Metallic High-Entropy Compound B.SUB.0.15.C.SUB.0.20.N.SUB.0.30.P.SUB.0.20.S.SUB.0.15

[0033] S1, 2 mmol of boric acid (H.sub.3BO.sub.3), 0.5 mmol of cyanuric chloride (C.sub.3Cl.sub.3N.sub.3), 0.5 mmol of ethoxy(pentafluoro)cyclotriphosphazene (C.sub.2H.sub.5F.sub.5N.sub.3OP.sub.3), and 2 mmol of thioacetamide (CH.sub.3CSNH.sub.2) were evenly dispersed in 80 mL of a mixed solvent of ethanol and water (volume ratio of 1:1) under stirring to obtain a precursor solution; and [0034] S2, the precursor solution was transferred into a 100 mL stainless steel reactor lined with polytetrafluoroethylene, and then reacted in an oven at 100? C. for 36 h; a resulting product was subjected to centrifugation and vacuum drying to obtain the B.sub.0.15C.sub.0.20N.sub.0.30P.sub.0.20S.sub.0.15, with molar proportions of component elements approximately as follows: B (15%), C (20%), N (30%), P (20%), and S (15%).

EXAMPLE 2

Non-Metallic High-Entropy Compound B.SUB.0.01.C.SUB.0.08.N.SUB.0.70.P.SUB.0.20.S.SUB.0.01

[0035] S1, 2 mmol of boric acid (H.sub.3BO.sub.3), 1 mmol of cyanuric chloride (C3Cl.sub.3N.sub.3), 1 mmol of ethoxy(pentafluoro)cyclotriphosphazene (C.sub.2H.sub.5F.sub.5N.sub.3OP.sub.3), and 2 mmol of thioacetamide (CH.sub.3CSNH.sub.2) were evenly dispersed in 80 mL of a mixed solvent of ethanol and water (volume ratio of 1:0.5) under stirring to obtain a precursor solution; and [0036] S2, the precursor solution was transferred into a 100 mL stainless steel reactor lined with polytetrafluoroethylene, and then reacted in an oven at 120? C. for 24 h; a resulting product was subjected to centrifugation and vacuum drying to obtain the B0.01C.sub.0.08N.sub.0.70P.sub.0.20S.sub.0.01, with molar proportions of component elements approximately as follows: B (1%), C (8%), N (70%), P (20%), and S (1%).

EXAMPLE 3

Non-Metallic High-Entropy Compound B.SUB.0.005.C.SUB.0.08.N.SUB.0.90.P.SUB.0.04.S.SUB.0.005

[0037] S1, 0.5 mmol of boric acid (H.sub.3BO.sub.3), 2 mmol of cyanuric chloride (C3Cl.sub.3N.sub.3), 2 mmol of ethoxy(pentafluoro)cyclotriphosphazene (C.sub.2H.sub.5F.sub.5N.sub.3OP.sub.3), and 0.5 mmol of thioacetamide (CH.sub.3CSNH.sub.2) were evenly dispersed in 80 mL of a mixed solvent of ethanol and water volume ratio of (1:1.5) under stirring to obtain a precursor solution; and [0038] S2, the precursor solution was transferred into a 100 mL stainless steel reactor lined with polytetrafluoroethylene, and then reacted in an oven at 160? C. for 12 h; a resulting product was subjected to centrifugation and vacuum drying to obtain the B.sub.0.005C.sub.0.05N.sub.0.90P.sub.0.04S.sub.0.005, with molar proportions of component elements approximately as follows: B (0.5%), C (5%), N (90%), P (4%), and S (0.5%).

EXAMPLE 4

Non-Metallic High-Entropy Compound B.SUB.0.05.C.SUB.0.12.N.SUB.0.20.P.SUB.0.15.S.SUB.0.12.Se.SUB.0.12.Si.SUB.0.12.O.SUB.0.12

[0039] S1, 1 mmol of boric acid (H.sub.3BO.sub.3), 0.5 mmol of cyanuric chloride (C.sub.3Cl.sub.3N.sub.3), 0.5 mmol of ethoxy(pentafluoro)cyclotriphosphazene (C.sub.2H.sub.5F.sub.5N.sub.3OP.sub.3), 1 mmol of thioacetamide (CH.sub.3CSNH.sub.2), 1 mmol of methyl-hydroselenide (CH.sub.4Se), and 1 mmol of trimethylsilyl acetate (C.sub.5H.sub.12OSi) were evenly dispersed in 80 mL of a mixed solvent of ethanol and water (volume ratio of 1:1) under stirring to obtain a precursor solution; and [0040] S2, the precursor solution was transferred into a 100 mL stainless steel reactor lined with polytetrafluoroethylene, and then reacted in an oven at 180? C. for 10 h; a resulting product was subjected to centrifugation and vacuum drying to obtain the B0.05C.sub.0.12N.sub.0.20P.sub.0.15S.sub.0.12Se.sub.0.12Si.sub.0.12O.sub.0.12, with molar proportions of component elements approximately as follows: B (5%), C (12%), N (20%), P (15%), S (12%), Se (12%), Si (12%), and O (12%).

EXAMPLE 5

Non-Metallic High-Entropy Compound B.SUB.0.13.C.SUB.0.20.N.SUB.0.30.P.SUB.0.20.S.SUB.0.12.I.SUB.0.05

[0041] S1, 2 mmol of boric acid (H.sub.3BO.sub.3), 0.5 mmol of cyanuric chloride (C3Cl.sub.3N.sub.3), 0.5 mmol of ethoxy(pentafluoro)cyclotriphosphazene (C.sub.2H.sub.5F.sub.5N.sub.3OP.sub.3), 2 mmol of thioacetamide (CH.sub.3CSNH.sub.2), and 2 mmol of hydrogen iodide (HI) were evenly dispersed in 80 mL of a mixed solvent of ethanol and water (volume ratio of 1:1) under stirring to obtain a precursor solution; and [0042] S2, the precursor solution was transferred into a 100 mL stainless steel reactor lined with polytetrafluoroethylene, and then reacted in an oven at 200? C. for 6 h; a resulting product was subjected to centrifugation and vacuum drying to obtain the B.sub.0.13C.sub.0.20N.sub.0.30P.sub.0.20S.sub.0.12I.sub.0.05, with molar proportions of component elements approximately as follows: B (13%), C (20%), N (30%), P (20%), S (12%), and I (5%).

EXAMPLE 6

Non-Metallic High-Entropy Compound B.SUB.0.10.C.SUB.0.22.N.SUB.0.33.P.SUB.0.23.S.SUB.0.12

[0043] S1, 1 mmol of boric acid (H.sub.3BO.sub.3), 0.5 mmol of carbamide (CH.sub.4N.sub.2O), 0.5 mmol of ethoxy(pentafluoro)cyclotriphosphazene (C.sub.2H.sub.5F.sub.5N.sub.3OP.sub.3), and 1 mmol of thioacetamide (CH.sub.3CSNH.sub.2) were ground and mixed uniformly to obtain a precursor solution; and [0044] S2, the precursor solution was calcined in a tubular furnace at 550? C. for 2 h under a nitrogen atmosphere to obtain the B.sub.0.15C.sub.0.20N.sub.0.30P.sub.0.20S.sub.0.15, with molar proportions of component elements approximately as follows: B (10%), C (22%), N (33%), P (23%), and S (12%).

EXAMPLE 7

Non-Metallic High-Entropy Compound B.SUB.0.07.C.SUB.0.12.N.SUB.0.70.P.SUB.0.08.S.SUB.0.03

[0045] S1, 1.2 mmol of boric acid (H.sub.3BO.sub.3), 1.0 mmol of cyanuric chloride (C.sub.3Cl.sub.3N.sub.3), 1.0 mmol of ethoxy(pentafluoro)cyclotriphosphazene (C.sub.2H.sub.5F.sub.5N.sub.3OP.sub.3), and 1.2 mmol of thioacetamide (CH.sub.3CSNH.sub.2) were evenly dispersed in 80 mL of a mixed solvent of ethanol and water (volume ratio of 1:1) under stirring to obtain a precursor solution; and [0046] S2, nitrogen with a flow rate of 50 mL/min was introduced into the precursor solution, and then introduced in the form of bubbling into a 550? C. tubular furnace to allow a reaction for 10 h to obtain the B.sub.0.07C.sub.0.12N.sub.0.7P.sub.0.08S.sub.0.03, with molar proportions of component elements approximately as follows: B (7%), C (12%), N (70%), P (8%), and S (3%).

EXAMPLE 8

Non-Metallic High-Entropy Compound B.SUB.0.10.C.SUB.0.05.N.SUB.0.8.P.SUB.0.04.S.SUB.0.01

[0047] S1, 1.5 mmol of boric acid (H.sub.3BO.sub.3), 0.5 mmol of cyanuric chloride (C.sub.3Cl.sub.3N.sub.3), 1.5 mmol of ethoxy(pentafluoro)cyclotriphosphazene (C.sub.2H.sub.5F.sub.5N.sub.3OP.sub.3), and 0.5 mmol of thioacetamide (CH.sub.3CSNH.sub.2) were evenly dispersed in 80 mL of a mixed solvent of ethanol and water (volume ratio of 1:1) under stirring to obtain a precursor solution; and [0048] S2, an electrochemical workstation was connected to the precursor solution to build a three-electrode system, where a reference electrode was an Ag/AgCl electrode, and a working electrode and a counter electrode were conductive glass; after 10 h of continuous reaction at a constant voltage of ?20 V, a product was obtained as the B.sub.0.10C.sub.0.05N.sub.0.8P.sub.0.04S.sub.0.01, with molar proportions of component elements approximately as follows: B (10%), C (5%), N (80%), P (4%), and S (1%).

EXAMPLE 9

Non-Metallic High-Entropy Compound C.SUB.0.09.Si.SUB.0.09.Se.SUB.0.04.F.SUB.0.26.Cl.SUB.0.26.Br.SUB.0.26

[0049] S1, 2 mmol of chlorine dioxide (ClO.sub.2), 2 mmol of hydrobromic acid (HBr), 2 mmol of hydrofluoric acid (HF), 2 mmol of methyl-hydroselenide (CH.sub.4Se), and 2 mmol of trimethylsilyl acetate (C.sub.5H.sub.12OSi) were evenly dispersed in 80 mL of a mixed solvent of ethanol and water (volume ratio of 1:1) under stirring to obtain a precursor solution; and [0050] S2, nitrogen with a flow rate of 50 mL/min was introduced into the precursor solution, and then introduced in the form of bubbling into a 700? C. tubular furnace to allow a reaction for 8 h to obtain the C.sub.0.09Si.sub.0.09Se.sub.0.04F.sub.0.26Cl.sub.0.26Br.sub.0.26, with molar proportions of component elements approximately as follows: C (9%), Si (9%), Se (4%), F (26%), Cl (26%), and S (26%).

Comparative Example 1

Conventional Photocatalyst/Electrocatalyst g-C.SUB.3.N.SUB.4

[0051] 5 mmol of carbamide (CH.sub.4N.sub.2O) was calcined at 500? C. for 2 h in a muffle furnace under an air atmosphere to obtain the g-C.sub.3N.sub.4.

Comparative Example 2

[0052] A catalyst prepared in Example 5 of Patent 201910475198.1 A preparation method of a multi-component non-metal-doped carbon nitride photocatalyst was used as a comparison. A specific preparation method thereof was as follows: [0053] S1, N,N-dimethylformamide (0.01 mol), hydrogen peroxide (0.02 mol), sodium metaphosphate (0.03 mol), and thioacetamide (0.05 mol) were mixed, added with 2 L of deionized water and then stirred at 600 rpm for 7 min to obtain a precursor solution; [0054] S2, dicyandiamide (0.05 mol) was added to the precursor solution, refluxed with heating and stirring for 2 h at 140? C., and then subjected to centrifugal separation to obtain a solid product; [0055] S3, the solid product was separately washed three times with absolute ethanol and deionized water in sequence, vacuum dried at 60? C. for 36 h, and then ground to obtain a powder; and [0056] S4, in the presence of nitrogen, the powder obtained in step S3 was heated to 700? C. at 6? C./min to allow calcination for 4 h, and then ball milled to obtain a quaternary non-metal-doped carbon nitride photocatalyst (TDCN) including nitrogen, oxygen, sulfur, and phosphorus.

Evaluation of Catalytic Activity

Test Example 1

Evaluation of Photocatalytic Reaction Activity

[0057] (1) Photocatalytic hydrogen production: 1.5 mg to 5.0 mg of the catalyst was ultrasonically dispersed in a 50 mL Pyrex bottle containing 4 mL of deionized water and an appropriate amount of 10 ppm methylene blue pollutant. The bottle was bubbled with Ar gas for 15 min to remove O.sub.2 and then reacted under the illumination of a 150 mW cm.sup.?2 Xe light source for a specific time. A production level of H.sub.2 was measured by gas chromatography, while a degradation rate of methyl orange was measured by a UV spectrophotometer. [0058] (2) Photocatalytic carbon dioxide reduction: 10 mg of the catalyst was dispersed on one side of an inner wall of the 50 mL Pyrex bottle, and 60 ?L of deionized water was added dropwise on a bottom of the bottle. The bottle was air-blown with CO.sub.2 for 15 min to remove O.sub.2 and add CO.sub.2. The bottle was reacted under light source irradiation of Xe lamp (150 mW cm.sup.?2) for 3 h. A resulting product CO was determined by gas chromatography. A band gap of the catalyst was calculated by measuring the UV-visible diffuse reflectance spectrum.

Test Example 2

Evaluation of Electrocatalytic Water Splitting Activity for Hydrogen Production

[0059] The electrocatalytic water splitting of catalytic material for hydrogen production was conducted in the three-electrode system. A reference electrode was Hg/HgO, a working electrode was a glassy carbon electrode, a counter electrode was a platinum electrode, and an electrolyte was a 1.0 mol/L KOH solution. The impedance spectra of the catalyst were uniformly tested at an overpotential of 100 mV and then fitted to obtain specific values. A higher impedance (R.sub.ct) value indicated less conductivity.

Test Example 3

Evaluation of Sodium-Ion Battery Activity

[0060] A sample, carbon black, and a sodium alginate binder were mixed at a mass ratio of 70:20:10 to obtain a slurry. In a test system, sodium foil was used as a counter electrode, a mixture of 1 mol/L NaPF.sub.6 and fluoroethylene carbonate/dimethyl carbonate (FEC/DMC, at a volume ratio of 1:1) was used as an electrolyte, and Celgard 3501 as a separator to assemble the sodium-ion battery.

TABLE-US-00001 TABLE 1 Evaluation results of photocatalytic hydrogen production activity coupled with organic pollutant degradation Reaction rate Complete degradation time Material (?mol g.sup.?1 h.sup.?1) of methylene blue (min) Example 1 1512.5 80 Example 2 972.3 90 Example 3 812.5 180 Example 4 876.4 120 Example 5 888.6 120 Example 6 935.4 110 Example 7 931.1 100 Example 8 833.4 160 Example 9 804.8 180 Comparative Example 1 202.2 360 Comparative Example 2 304.5 280

TABLE-US-00002 TABLE 2 Evaluation results of photocatalytic carbon dioxide reduction activity Material Band gap (eV) Reaction rate (?mol g.sup.?1 h.sup.?1) Example 1 1.8 36.5 Example 2 2.0 28.4 Example 3 1.3 25.2 Example 4 0.3 27.5 Example 5 1.4 24.3 Example 6 1.3 23.6 Example 7 2.2 24.1 Example 8 1.7 28.1 Example 9 3.1 25.4 Comparative Example 1 2.7 12.6 Comparative Example 2 2.5 14.3

TABLE-US-00003 TABLE 3 Evaluation results of electrocatalytic water splitting activity for hydrogen production Impedance Overpotential at 10 mA cm.sup.?2 Material (R.sub.ct, ?) (mV) Example 1 9.4 81.2 Example 2 10.1 84.3 Example 3 6.3 88.1 Example 4 1.1 85.6 Example 5 8.6 90.7 Example 6 8.2 96.4 Example 7 12.3 90.6 Example 8 9.2 84.5 Example 9 13.4 91.2 Comparative Example 1 18.2 300.5 Comparative Example 2 15.3 188.6

TABLE-US-00004 TABLE 4 Evaluation results of sodium-ion battery activity Material Specific capacity (mAh g.sup.?1) Example 1 670.3 Example 7 602.5 Comparative Example 1 161.4 Comparative Example 2 93.3

[0061] To sum up, in the present disclosure: compared with the photoelectrocatalysts of Comparative Examples 1 to 2, the non-metallic high-entropy compounds prepared in Examples 1 to 9 showed a catalytic reaction activity for hydrogen production by high-efficiency photocatalytic/electrocatalytic water splitting, carbon dioxide reduction, or organic pollutant degradation.

[0062] Finally, it should be noted that the above embodiments are merely intended to describe the technical solutions of the present disclosure, rather than to limit the present disclosure. Although the present disclosure is described in detail with reference to the above embodiments, persons of ordinary skill in the art should understand that they may still make modifications to the technical solutions described in the above embodiments or make equivalent replacements to some or all technical features thereof, without departing from the essence of the technical solutions in the embodiments of the present disclosure.