Quantum dot material, and preparation method and use thereof

Abstract

Provided are a quantum dot material, a preparation method and use thereof. The quantum material includes a quantum dot, and a first cladding layer and a second cladding clad outside of the quantum dot, wherein the first cladding layer is located between the quantum dot and the second cladding layer. The quantum dot material provided herein has good water and oxygen barrier properties and good stability.

Claims

1. A preparation method for a quantum dot material, comprising: (1) mixing a quantum dot solution and a precursor material of a first cladding layer, cladding by a reaction to obtain a quantum dot material with the first cladding layer; and (2) depositing a second cladding layer outside the quantum dot material with the first cladding layer by an atomic layer deposition method to obtain the quantum dot material; wherein the quantum dot solution has a concentration of 1 mg/mL to 200 mg/mL, the precursor material is added in an amount of 0.1% to 10%; the quantum dot material, comprising a quantum dot, and a first cladding layer and a second cladding layer clad outside of the quantum dot; wherein the first cladding layer is located between the quantum dot and the second cladding layer.

2. The preparation method according to claim 1, wherein the first cladding layer is made of any one or a combination of at least two materials selected from a group consisting of SiO.sub.2, ZnO, Al.sub.2O.sub.3, TiO.sub.2, Fe.sub.3O.sub.4, and Fe.sub.2O.sub.3.

3. The preparation method according to claim 1, wherein the first cladding layer has a thickness of 5 nm to 100 μm.

4. The preparation method according to claim 1, wherein the quantum dot is any one or a combination of at least two selected from a group consisting of CdSe, CdTe, CdS, ZnSe, CdTe, CuInS.sub.2, InP, CsPbX.sub.3, CuZnSe, and ZnMnSe, wherein X is a halogen.

5. The preparation method according to claim 1, wherein the second cladding layer is made of any one or a combination of at least two materials selected from a group consisting of Al.sub.2O.sub.3, ZrO.sub.2, ZnO, ZnS, and TiO.sub.2.

6. The preparation method according to claim 1, wherein the second cladding layer has a thickness of 1 nm to 100 μm.

7. The preparation method according to claim 1, wherein the precursor material is any one or a combination of at least two selected from a group consisting of tetramethoxysilane, tetraethoxysilane, zinc acetylacetonate, aluminum acetylacetonate, tetrabutyl titanate, and iron acetylacetonate.

8. The preparation method according to claim 1, wherein the atomic layer deposition method comprises: (A) in a vacuum environment, reacting the quantum dot material with the first cladding layer with a first precursor at a reaction temperature; and (B) reacting with a second precursor; and repeating step (A) and step (B) in sequence to obtain the quantum dot material.

9. The preparation method according to claim 8, wherein the first precursor in step (A) comprises any one or a combination of at least two selected from a group consisting of trimethylaluminum, triethylaluminum, tetrakis(dimethylamino)zirconium, biscyclopentadienyl dimethyl zirconium, dimethyl zinc, diethyl zinc, and tetramethoxy titanium.

10. The preparation method according to claim 8, wherein the second precursor in step (B) comprises any one or a combination of at least two selected from a group consisting of water, hydrogen sulfide, methanol, ethanol, and ammonia.

11. The preparation method according to claim 8, wherein the reaction temperature is 60° C. to 120° C.

12. The preparation method according to claim 8, wherein performing step (A) and step (B) once is referred as one reaction cycle, and the one reaction cycle lasts for 2 min to 20 min.

13. The preparation method according to claim 8, wherein the reaction cycle is repeated 10 times to 500 times.

14. The preparation method according to claim 8, wherein a cleaning gas is required to be introduced to clean the reaction environment both after the reaction with the first precursor is finished and after the reaction with the second precursor is finished.

15. The preparation method according to claim 1, comprising: (I) mixing a quantum dot solution with a concentration of 1 mg/mL to 200 mg/mL and a precursor material of a first cladding layer, cladding by a reaction to obtain a quantum dot material with a first cladding layer; (II) in a vacuum environment, reacting the quantum dot material with the first cladding layer with a first precursor at 60° C. to 200° C.; (III) after the reaction with the first precursor is finished, introduce a cleaning gas to clean the reaction environment; (IV) introducing a seco9nd precursor to react: and (V) after the reaction with the second precursor is finished; introduce a cleaning gas to clean the reaction environment; and repeating steps (II) to step (V) in sequence 10 times to 500 times to obtain the quantum dot material.

Description

DETAILED DESCRIPTION

(1) The technical solutions of the present disclosure are further described below through specific embodiments. Those skilled in the art should understand that the embodiments are merely used to help understand the present disclosure and should not be regarded as specific limitations on the present disclosure.

EXAMPLE 1

(2) A quantum dot material was prepared as follows:

(3) (1) 20 mL of a solution of CdSe in toluene with a concentration of 1 mg/mL was prepared. 20 μL of a precursor, i.e. tetramethoxysilane was added and stirred. Under the action of water in the air, the tetramethoxysilane was slowly hydrolyzed into silicon dioxide which was clad on the surface of the quantum dot. The clad quantum dot was centrifuged and lyophilized to obtain CdSe@SiO.sub.2 powder (SiO.sub.2-clad CdSe powder).

(4) (2) The quantum dot powder was placed in the cavity of an ALD device, and the cavity was vacuumed and heated to 60° C. Trimethylaluminum gas was loaded through N.sub.2 to react with groups on the surface of the quantum dot powder to be adsorbed, and then N.sub.2 was introduced again to remove excess trimethylaluminum and by-products. Water vapor was then loaded through N.sub.2, and adsorbed onto the surface of the first precursor and reacted with the first precursor, and then N.sub.2 was introduced again to remove excess water vapor and by-products.

(5) This was one cycle which lasted 2 min. The cycle was repeated 500 times to obtain CdSe@SiO.sub.2@Al.sub.2O.sub.3 powder.

EXAMPLE 2

(6) A quantum dot material was prepared as follows:

(7) (1) 40 mL of a solution of InP in chloroform with a concentration of 10 mg/mL was prepared. 50 μL of a precursor, i.e. tetrabutyl titanate and 50 μL of water were added and stirred. Under the action of the water, the tetrabutyl titanate was slowly hydrolyzed into titanium dioxide which was clad on the surface of the quantum dot. The clad quantum dot was centrifuged, deposited and lyophilized to obtain InP@TiO.sub.2 powder.

(8) (2) The quantum dot powder was placed in the cavity of an ALD device, and the cavity was vacuumed and heated to 60° C. Triethylaluminum gas was loaded through N.sub.2 to react with groups on the surface of the powder of the quantum dot to be adsorbed, and then N.sub.2 was introduced again to remove excess triethylaluminum and by-products. Water vapor was then loaded through N.sub.2, adsorbed onto the surface of the first precursor and reacted with the first precursor, and then N.sub.2 was introduced again to remove excess water vapor and by-products.

(9) This was a cycle which lasted 3 min. The cycle was repeated 250 times to obtain InP@TiO.sub.2@Al.sub.2O.sub.3 powder.

EXAMPLE 3

(10) A quantum dot material was prepared as follows:

(11) (1) 60 mL of a solution of CsPbBr.sub.3 in toluene with a concentration of 20 mg/mL was prepared. 100 μL of a precursor, i.e. tetraethoxysilane was added and stirred. Under the action of water in the air, the tetraethoxysilane was slowly hydrolyzed into zirconium dioxide which was clad on the surface of the quantum dot. The clad quantum dot was centrifuged, and the obtained deposit was lyophilized to obtain CsPbBr.sub.3@SiO.sub.2 powder.

(12) (2) The quantum dot powder was placed in the cavity of an ALD device, and the cavity was vacuumed and heated to 60° C. Biscyclopentadienyl dimethyl zirconium was loaded through N.sub.2 to react with groups on the surface of the powder of the quantum dot to be adsorbed, and then N.sub.2 was introduced again to remove excess biscyclopentadienyl dimethyl zirconium and by-products. Water vapor was then loaded through N.sub.2, adsorbed onto the surface of the first precursor and reacted with the first precursor, and then N.sub.2 was introduced again to remove excess water vapor and by-products.

(13) This was a cycle which lasted 4 min. The cycle was repeated 100 times to obtain CsPbBr.sub.3@SiO.sub.2@ZrO.sub.2 powder.

EXAMPLE 4

(14) A quantum dot material was prepared as follows:

(15) (1) 20 mL of a solution of CuInS.sub.2 in toluene with a concentration of 200 mg/mL was prepared. 200 μL of a precursor, i.e. iron acetylacetonate was added and stirred. Under the action of water in the air, the iron acetylacetonate was slowly hydrolyzed into iron trioxide which was clad on the surface of the quantum dot. The clad quantum dot was centrifuged, and the obtained deposit was lyophilized to obtain CuInS.sub.2@Fe.sub.2O.sub.3 powder.

(16) (2) The quantum dot powder was placed in the cavity of an ALD device, and the cavity was vacuumed and heated to 60° C. Diethyl zinc gas was loaded through N.sub.2 to react with groups on the surface of the powder of the quantum dot to be adsorbed, and then N.sub.2 was introduced again to remove excess diethyl zinc and by-products. Hydrogen sulfide gas was then loaded through N.sub.2, adsorbed onto the surface of the first precursor and reacted with the first precursor, and then N.sub.2 was introduced again to remove the excess hydrogen sulfide gas and by-products.

(17) This was a cycle which lasted 6 min. The cycle was repeated 100 times to obtain CuInS.sub.2@Fe.sub.2O.sub.3@ZnS powder.

EXAMPLE 5

(18) A quantum dot material was prepared as follows:

(19) (1) 20 mL of a solution of CdSe in toluene with a concentration of 20 mg/mL was prepared. 100 μL of a precursor, i.e. tetramethoxysilane was added and stirred. Under the action of water in the air, the tetramethoxysilane was slowly hydrolyzed into silicon dioxide which was clad on the surface of the quantum dot. The clad quantum dot was centrifuged, and the obtained deposit was lyophilized to obtain CdSe@SiO.sub.2 powder.

(20) (2) The quantum dot powder was placed in the cavity of an ALD device, and the cavity was vacuumed and heated to 80° C. Trimethylaluminum gas was loaded through N.sub.2 to react with groups on the surface of the powder of the quantum dot to be adsorbed, and then N.sub.2 was introduced again to remove excess trimethylaluminum and by-products. Water vapor was then loaded through N.sub.2, adsorbed onto the surface of the first precursor and reacted with the first precursor, and then N.sub.2 was introduced again to remove excess water vapor and by-products.

(21) This was a cycle which lasted 10 min. The cycle was repeated 50 times to obtain CdSe@SiO.sub.2Al.sub.2O.sub.3 powder.

EXAMPLE 6

(22) A quantum dot material was prepared as follows:

(23) (1) 20 mL of a solution of CdSe in toluene with a concentration of 20 mg/mL was prepared. 100 μL of a precursor, i.e. tetramethoxysilane was added and stirred. Under the action of water in the air, the tetramethoxysilane was slowly hydrolyzed into silicon dioxide which was clad on the surface of the quantum dot. The clad quantum dot was centrifuged, and the obtained deposit was lyophilized to obtain CdSe@SiO.sub.2 powder.

(24) (2) The quantum dot powder was placed in the cavity of an ALD device, and the cavity was vacuumed and heated to 100° C. Trimethylaluminum gas was loaded through N.sub.2 to react with groups on the surface of the powder of the quantum dot to be adsorbed, and then N.sub.2 was introduced again to remove excess trimethylaluminum and by-products. Water vapor was then loaded through N.sub.2, adsorbed onto the surface of the first precursor and reacted with the first precursor, and then N.sub.2 was introduced again to remove excess water vapor and by-products.

(25) This was a cycle which lasted 15 min. The cycle was repeated 20 times to obtain CdSe@SiO.sub.2@Al.sub.2O.sub.3 powder.

EXAMPLE 7

(26) A quantum dot material was prepared as follows:

(27) (1) 20 mL of a solution of CdSe in toluene with a concentration of 20mg/mL was prepared. 100 μL of a precursor, i.e. tetramethoxysilane was added and stirred. Under the action of water in the air, the tetramethoxysilane was slowly hydrolyzed into silicon dioxide which was clad on the surface of the quantum dot. The clad quantum dot was centrifuged, and the obtained deposit was lyophilized to obtain CdSe@SiO.sub.2 powder.

(28) (2) The quantum dot powder was placed in the cavity of an ALD device, and the cavity was vacuumed and heated to 150° C. Trimethylaluminum gas was loaded through N.sub.2 to react with groups on the surface of the powder of the quantum dot to be adsorbed, and then N.sub.2 was introduced again to remove excess trimethylaluminum and by-products. Water vapor was then loaded through N.sub.2, adsorbed onto the surface of the first precursor and reacted with the first precursor, and then N.sub.2 was introduced again to remove excess water vapor and by-products.

(29) This was a cycle which lasted 20 min. The cycle was repeated 10 times to obtain CdSe@SiO.sub.2@Al.sub.2O.sub.3 powder.

EXAMPLE 8

(30) A quantum dot material was prepared as follows:

(31) (1) 20 mL of a solution of CdSe in toluene with a concentration of 20 mg/mL was prepared. 100 μL of a precursor, i.e. tetramethoxysilane was added and stirred. Under the action of water in the air, the tetramethoxysilane was slowly hydrolyzed into silicon dioxide which was clad on the surface of the quantum dot. The clad quantum dot was centrifuged, and the obtained deposit was lyophilized to obtain CdSe@SiO.sub.2 powder.

(32) (2) The quantum dot powder was placed in the cavity of an ALD device, and the cavity was vacuumed and heated to 200° C. Trimethylaluminum gas was loaded through N.sub.2 to react with groups on the surface of the powder of the quantum dot to be adsorbed, and then N.sub.2 was introduced again to remove excess trimethylaluminum and by-products. Water vapor was then loaded through N.sub.2, adsorbed onto the surface of the first precursor and reacted with the first precursor, and then N.sub.2 was introduced again to remove excess water vapor and by-products.

(33) This was a cycle which lasted 20 min. The cycle was repeated 10 times to obtain CdSe@SiO.sub.2@Al.sub.2O.sub.3 powder.

EXAMPLE 9

(34) The difference from Example 1 was that the tetramethoxysilane was replaced with aluminum acetylacetonate.

COMPARATIVE EXAMPLE 1

(35) The difference from Example 1 was that only step (1) was performed and step (2) was not performed to obtain a quantum dot material.

COMPARATIVE EXAMPLE 2

(36) The difference from Example 1 was that only step (2) was performed 500 times and step (1) was not performed to obtain a quantum dot material.

(37) Performance Test

(38) A performance test was performed on quantum dot materials provided by Examples 1 to 9 and Comparative example 1 to 2 by the following method:

(39) (1) Light aging test: the quantum dot materials were lit on a pure blue LED, with a blue light wavelength of 450 nm, a power of about 38 mW, an inner slot area of 0.047 cm.sup.2, and an optical power density of 808 mW/cm.sup.2; an ambient temperature of 20° C., and humidity of about 80%; and a concentration of quantum dot glue of 100 mg/g. Light conversion rates of the quantum dot materials were tested using an ATA500 single-integrating sphere after lit for 240 h and 1000 h to calculate aging/decaying rates.

(40) Test results are listed in table 1.

(41) TABLE-US-00001 TABLE 1 Time Aging/Decaying Time Aging/Decaying Sample (h) (%) (h) (%) Example 1 240 3.9% 1000 16.7% Example 2 240 4.1% 1000 18.9% Example 3 240 4.3% 1000 17.6% Example 4 240 4.6% 1000 19.3% Example 5 240 3.6% 1000 16.8% Example 6 240 4.2% 1000 18.9% Example 7 240 3.6% 1000 19.6% Example 8 240 5.1% 1000 17.3% Example 9 240 3.3% 1000 18.2% Comparative 240  40% 1000 .sup. 70% example 1 Comparative 240  60% 1000 .sup. 85% example 2

(42) It can be known from the examples and the performance test that the quantum dot materials provided by the present disclosure have excellent water and oxygen barrier properties and good stability. Light conversion efficiency of the quantum dot materials is maintained above 80% when they are lit for 1000 h under high-intensity blue light.

(43) It can be seen from the comparison between Example 1 and Example 9 that the first cladding layer provided by the present disclosure is preferably a silicon dioxide cladding layer, which can make the final quantum dot material more stable. It can be seen from the comparison between Example 1 and Comparative examples 1 and 2 that the quantum dot material having two cladding layers provided by the present disclosure has better water and oxygen barrier properties and better stability.

(44) The applicant has stated that although the quantum dot material, and the preparation method and use thereof in the present disclosure are described through the embodiments described above, the present disclosure is not limited to the detailed methods described above, which means that implementation of the present disclosure does not necessarily depend on the detailed methods described above. It should be apparent to those skilled in the art that any improvements made to the present disclosure, and equivalent replacements of various raw materials, the addition of adjuvant ingredients and the selection of specific manners, etc. in the present disclosure all fall within the protection scope and the scope of disclosure of the present disclosure.