A photocatalytic material and a method for preparing the same

Abstract

The application discloses a kind of photocatalytic material and preparation method thereof, comprising the following steps: cesium chloride, lead chloride and manganese chloride are ground and mixed according to certain proportion, and perovskite quantum dot precursor is obtained;Perovskite quantum dot precursor and molecular sieve carrier are ground and mixed according to certain proportion, and mixture material is obtained;After calcining in inert atmosphere, the photocatalytic material of the application is obtained after curing;The chemical general formula of the photocatalytic material of the application is CsPb 1‑x Mn x Cl3@LTA (x=0, 0.2, 0.4, 0.6, 0.8);The photocatalytic material prepared by the method has the characteristics of simple process, does not contain any organic solvent, is environment-friendly, is convenient for large-scale synthesis, has good stability and excellent photocatalytic performance, and has good industrialization application prospect.

Description

Technical Field

[0001] This invention belongs to the field of photocatalytic materials, specifically relating to a photocatalytic material and its preparation method. Background Technology

[0002] With rapid population and industrialization, global energy supply has increased dramatically. The vast majority of global energy comes from fossil fuels, and the use of fossil fuels causes severe CO2 emissions. Excessive CO2 emissions lead to a series of problems, including global warming, glacial melting, and biodiversity loss. Therefore, the conversion and utilization of CO2 is urgently needed. All-inorganic perovskite CsPbX3 (X = Cl, Br, I) quantum dots (PQDs) are considered excellent candidate materials for photocatalysts due to their high defect tolerance, suitable band structure, and long carrier lifetime. However, severe radiative recombination, extremely poor stability, and poor CO2 capture ability limit their development and application in the field of photocatalysis.

[0003] To address issues such as improving the stability of perovskite quantum dots (PQDs), suppressing radiative recombination, and enhancing CO2 capture capabilities, researchers have explored numerous methods. Existing techniques include solution-based preparation of PQDs-SiO2 core-shell composite materials to improve the water and oxygen resistance of PQDs. This method involves hydrolyzing tetraethyl orthosilicate into SiO2 to encapsulate PQDs and improve stability. However, this method completely encapsulates the PQDs within SiO2, severely limiting their applications. Another existing technique involves embedding perovskite quantum dots within zeolites to enhance water stability, but this requires the use of organic solvents to transport ions into the zeolite, making the process complex and environmentally unfriendly. A further existing technique involves coating perovskite quantum dots with polypyrrole to improve stability and photocatalytic performance, but this method also inevitably uses large amounts of organic solvents.

[0004] The methods described above only improve the stability of PQDs; the problems of suppressing radiative recombination and enhancing the CO2 capture capacity of PQDs remain unresolved, thus limiting the widespread application of PQDs. Therefore, it is necessary to develop a photocatalytic material and its preparation method to address these issues. Summary of the Invention

[0005] The purpose of this invention is to provide a photocatalytic material and its preparation method, which can improve the problems of weak CO2 capture ability of PQDs and difficulty in suppressing radiative recombination of PQDs while enhancing the stability of PQDs.

[0006] In a first aspect, the present invention provides a photocatalytic material comprising a perovskite quantum dot precursor and a molecular sieve support in a mass ratio of 1:(1-4), wherein the quantum dot precursor comprises a cesium salt and a mixed salt in a molar ratio of (1-2):(1-3), wherein the mixed salt comprises a lead salt and a manganese salt in a molar ratio of (1-2):(1-4).

[0007] Secondly, the present invention provides a method for preparing a photocatalytic material, comprising the following steps:

[0008] The perovskite quantum dot precursor and the molecular sieve support were mixed and ground to obtain a mixture.

[0009] The mixture is calcined in a non-oxidizing atmosphere within a first temperature range to obtain a photocatalytic precursor; wherein the minimum value of the first temperature range is greater than or equal to the melting point of the perovskite quantum dot precursor, and the maximum value of the first temperature range is less than the decomposition temperature of the molecular sieve support.

[0010] The photocatalytic precursor is cured to obtain the photocatalytic material.

[0011] Optionally, before performing the step of mixing and milling the perovskite quantum dot precursor with the molecular sieve support, the following steps are performed:

[0012] A perovskite quantum dot precursor is prepared by uniformly mixing cesium salt and mixed salt in a molar ratio of (1-2):(1-3); wherein the mixed salt is a mixture of lead salt and manganese salt in a molar ratio of (1-2):(1-4).

[0013] Optionally, when calcining the mixture in a non-oxidizing atmosphere within a first temperature range, the non-oxidizing atmosphere includes nitrogen and an inert gas.

[0014] Optionally, when calcining the mixture in a non-oxidizing atmosphere within a first temperature range, the first temperature range is 500-700°C.

[0015] Optionally, when maintaining the photocatalytic precursor, the ambient temperature for maintenance is controlled at 20-50℃.

[0016] Optionally, when maintaining the photocatalytic precursor, the humidity of the maintenance environment is controlled at 5-95%.

[0017] Optionally, when curing the photocatalytic precursor, the curing time is 5-20 days.

[0018] Optionally, the photocatalytic materials provided by this invention can be applied in the field of photocatalysis.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) The preparation method provided by the present invention involves calcining the raw materials after mixing them, and then using a vapor deposition crystallization method to allow the PQDs precursor to enter the LTA channels in a gaseous form at high temperature, thereby obtaining a photocatalytic material of LTA-coated perovskite quantum dots.

[0021] (2) The preparation method provided by the present invention improves the water, light and heat stability of PQDs by utilizing the channels of LTA to block the erosion of liquid water and ultraviolet light;

[0022] (3) The preparation method provided by the present invention enhances the CO2 capture capability of PQDs by utilizing the porous structure of LTA;

[0023] (4) The preparation method provided by the present invention reduces the application of heavy metal lead by doping with manganese, thereby further protecting the environment, inhibiting radiation recombination, and improving photocatalytic performance;

[0024] (5) The preparation method provided by the present invention does not use any organic solvents, is environmentally friendly, and is easy to synthesize on a large scale;

[0025] (6) The photocatalytic material prepared in this invention exhibits enhanced fluorescence after being cured in an environment with a temperature of 20°C and a humidity of 60±5%. Attached Figure Description

[0026] Figure 1 The preparation flow chart of the photocatalytic material provided by the present invention;

[0027] Figure 2 CsPb obtained in Examples 23-27 1-x Mn x X-ray diffraction pattern of Cl3@LTA;

[0028] Figure 3 CsPbCl3@LTA prepared in Example 23 and CsPb prepared in Example 26 0.4 Mn 0.6 Transmission electron microscopy image of Cl3@LTA;

[0029] Figure 4 CsPb prepared in Examples 23-27 1-x Mn x The yields of CO and CH4 obtained when carbon dioxide is reduced by Cl3@LTA;

[0030] Figure 5 CsPb prepared in Example 26 0.4 Mn 0.6 Validation results of the catalytic performance of Cl3@LTA-26 in the cyclic catalysis of carbon dioxide;

[0031] Figure 6 CsPb prepared in Example 26 0.4 Mn 0.6 CsPb prepared by Cl3@LTA-26 and Comparative Example 1 0.2 Mn 0.8 N2 adsorption-desorption curves of Cl3QDs;

[0032] Figure 7 Fluorescence spectra of CsPbCl3@LTA-23 prepared in Example 23 before curing and after curing in an environment with a temperature of 20°C and a humidity of 60±5%. Detailed Implementation

[0033] The present invention will be further described in conjunction with the accompanying drawings.

[0034] In a first aspect, the present invention provides a photocatalytic material comprising a perovskite quantum dot precursor and a molecular sieve support in a mass ratio of 1:(1-4), wherein the perovskite quantum dot precursor comprises a cesium salt and a mixed salt in a molar ratio of (1-2):(1-3), wherein the mixed salt comprises a lead salt and a manganese salt in a molar ratio of (1-2):(1-4).

[0035] Secondly, see Figure 1 This invention provides a method for preparing a photocatalytic material, comprising the following steps:

[0036] D1. After mixing and grinding the perovskite quantum dot precursor and the molecular sieve support, a mixture is obtained.

[0037] D2. The mixture is calcined in a non-oxidizing atmosphere within a first temperature range to obtain a photocatalytic precursor; wherein the minimum value of the first temperature range is greater than or equal to the melting point of the perovskite quantum dot precursor, and the maximum value of the first temperature range is less than the decomposition temperature of the molecular sieve support.

[0038] D3. The photocatalytic precursor is cured to obtain the photocatalytic material.

[0039] In some embodiments, the first temperature range is 500-700°C. In practice, the temperature range of the first temperature range depends on the melting point of the perovskite quantum dot precursor and the decomposition temperature of the molecular sieve support.

[0040] In some embodiments, the grinding is performed under an infrared drying lamp.

[0041] In some embodiments, the molecular sieve is an aluminosilicate molecular sieve (LTA).

[0042] Specifically, the aluminosilicate molecular sieve has a particle size of 1-5 μm, an average pore size of 0.56-0.58 nm, and a decomposition temperature of 700℃.

[0043] In some embodiments, the cesium salt is specifically cesium chloride, the lead salt is specifically lead chloride, and the manganese salt is specifically manganese chloride.

[0044] In some embodiments, lead chloride and manganese chloride are mixed to form a mixed salt before the mixing and grinding is performed when preparing perovskite quantum dot precursors.

[0045] In some embodiments, the non-oxidizing atmosphere includes nitrogen (N2) and inert gases.

[0046] In fact, the non-oxidizing atmosphere mainly used in the examples is N2.

[0047] In fact, calcination is carried out in an alumina crucible.

[0048] Specifically, the time for introducing a non-oxidizing atmosphere before calcination is 10-30 minutes.

[0049] Specifically, the rate of introducing the non-oxidizing atmosphere is 0.1-0.5℃ / min.

[0050] In some embodiments, the calcination temperature is 500-700°C.

[0051] Specifically, the heating rate during calcination is controlled at 5-10℃ / min.

[0052] Specifically, the holding time during calcination should be controlled between 30 and 90 minutes.

[0053] Specifically, the ambient temperature for maintenance should be controlled between 20-50℃, and the ambient humidity should be controlled between 5-95%.

[0054] Specifically, the optimal maintenance period is 5-20 days.

[0055] Example 1

[0056] Example 1 of this invention provides a method for preparing a photocatalytic material, comprising the following steps:

[0057] D0. Under an infrared drying lamp, CsCl and a mixed salt were uniformly ground and mixed at a molar ratio of 2:1 to obtain the PQDs precursor; wherein the molar ratio of PbCl2 to MnCl2 in the mixed salt was 1:0.

[0058] D1. Under an infrared drying lamp, the PQDs precursor and LTA are uniformly ground and mixed at a mass ratio of 1:2 to obtain a mixture.

[0059] D2. Place the mixture in an alumina crucible and transfer it to a tube furnace under nitrogen atmosphere. Heat the mixture from room temperature to 650°C at a heating rate of 5°C / min and calcine it at that temperature for 60 minutes. Then, allow it to cool naturally to room temperature to obtain the photocatalytic precursor.

[0060] D3. The photocatalytic precursor was transferred to a curing environment with an ambient temperature of 20℃ and an ambient humidity of 60±5% and cured for 15 days to obtain the photocatalytic material, which was named CsPbCl3@LTA-1.

[0061] Example 2

[0062] Example 2 of this invention provides a method for preparing a photocatalytic material, which differs from Example 1 in that: in step S0, the molar ratio of CsCl and mixed salt in the PQDs precursor is 1:2; the photocatalytic material prepared in Example 2 is named CsPbCl3@LTA-2.

[0063] Example 3

[0064] Example 3 of this invention provides a method for preparing a photocatalytic material, which differs from Example 1 in that: in step S0, the molar ratio of CsCl and mixed salt in the PQDs precursor is 1:3; the photocatalytic material prepared in Example 3 is named CsPbCl3@LTA-3.

[0065] Example 4

[0066] Example 4 of this invention provides a method for preparing a photocatalytic material, which differs from Example 1 in that: in step S0, the molar ratio of CsCl and mixed salt in the PQDs precursor is changed to 1:1, and in step S2, the calcination temperature is changed to 500℃, while other conditions are the same as in Example 1; the photocatalytic material prepared in Example 4 is named CsPbCl3@LTA-4.

[0067] Example 5

[0068] Example 5 of this invention provides a method for preparing a photocatalytic material. The difference from Example 4 is that the calcination temperature in step S2 is changed to 550°C, while other conditions are the same as in Example 4. The photocatalytic material prepared in Example 5 is named CsPbCl3@LTA-5.

[0069] Example 6

[0070] Example 6 of this invention provides a method for preparing a photocatalytic material. The difference from Example 4 is that the calcination temperature in step S2 is changed to 600°C, while other conditions are the same as in Example 4. The photocatalytic material prepared in Example 6 is named CsPbCl3@LTA-6.

[0071] Example 7

[0072] Example 7 of this invention provides a method for preparing a photocatalytic material. The difference from Example 4 is that the calcination temperature in step S2 is changed to 700°C, while other conditions are the same as in Example 4. The photocatalytic material prepared in Example 7 is named CsPbCl3@LTA-7.

[0073] Example 8

[0074] Example 8 of this invention provides a method for preparing a photocatalytic material. The difference from Example 4 is that the mass ratio of PQDs precursor to LTA in step S1 is changed to 1:1, the calcination temperature in step S2 is changed to 650℃, and other conditions are the same as in Example 4. The photocatalytic material prepared in Example 8 is named CsPbCl3@LTA-8.

[0075] Example 9

[0076] Example 9 of this invention provides a method for preparing a photocatalytic material. The difference from Example 8 is that the mass ratio of PQDs precursor to LTA in step S1 is changed to 1:3, while other conditions are the same as in Example 8. The photocatalytic material prepared in Example 9 is named CsPbCl3@LTA-9.

[0077] Example 10

[0078] Example 10 of this invention provides a method for preparing a photocatalytic material. The difference from Example 8 is that the mass ratio of PQDs precursor to LTA in step S1 is changed to 1:4, while other conditions are the same as in Example 8. The photocatalytic material prepared in Example 10 is named CsPbCl3@LTA-10.

[0079] Example 11

[0080] Example 11 of this invention provides a method for preparing a photocatalytic material. The difference from Example 8 is that the mass ratio of PQDs precursor to LTA in step S1 is changed to 1:2, the calcination time with an inert atmosphere in step S2 is changed to 10 min, and other conditions are the same as in Example 10. The photocatalytic material prepared in Example 11 is named CsPbCl3@LTA-11.

[0081] Example 12

[0082] Example 12 of this invention provides a method for preparing a photocatalytic material. The difference from Example 11 is that the calcination time in step S2 with an inert atmosphere is changed to 20 min, while other conditions are the same as in Example 11. The photocatalytic material prepared in Example 12 is named CsPbCl3@LTA-12.

[0083] Example 13

[0084] Example 13 of this invention provides a method for preparing a photocatalytic material. The difference from Example 11 is that the calcination time in step S2 with an inert atmosphere is changed to 40 min, while other conditions are the same as in Example 11. The photocatalytic material prepared in Example 13 is named CsPbCl3@LTA-13.

[0085] Example 14

[0086] Example 14 of this invention provides a method for preparing a photocatalytic material. The difference from Example 11 is that the ventilation rate in step S2 is changed to 0.1 L / min, while other conditions are the same as in Example 11. The photocatalytic material prepared in Example 14 is named CsPbCl3@LTA-14.

[0087] Example 15

[0088] Example 15 of this invention provides a method for preparing a photocatalytic material. The difference from Example 11 is that the ventilation rate in step S2 is changed to 0.3 L / min, while other conditions are the same as in Example 11. The photocatalytic material prepared in Example 15 is named CsPbCl3@LTA-15.

[0089] Example 16

[0090] Example 16 of this invention provides a method for preparing a photocatalytic material. The difference from Example 11 is that the ventilation rate of step S2 is changed to 0.4 L / min, while other conditions are the same as in Example 11. The photocatalytic material prepared in Example 16 is named CsPbCl3@LTA-16.

[0091] Example 17

[0092] Example 16 of this invention provides a method for preparing a photocatalytic material, which differs from Example 11 in that the ventilation rate in step S2 is changed to 0.5 L / min, while other conditions are the same as in Example 11; the photocatalytic material prepared in Example 17 is named CsPbCl3@LTA-17.

[0093] Example 18

[0094] Example 16 of this invention provides a method for preparing a photocatalytic material, which differs from Example 11 in that the heating rate in step S2 is changed to 1℃ / min, while other conditions are the same as in Example 11; the photocatalytic material prepared in Example 18 is named CsPbCl3@LTA-18.

[0095] Example 19

[0096] Example 19 of this invention provides a method for preparing a photocatalytic material. The difference from Example 11 is that the heating rate in step S2 is changed to 10℃ / min, while other conditions are the same as in Example 11. The photocatalytic material prepared in Example 19 is named CsPbCl3@LTA-19.

[0097] Example 20

[0098] Example 20 of this invention provides a method for preparing a photocatalytic material. The difference from Example 11 is that the heat preservation time in step S2 is changed to 30 min, while other conditions are the same as in Example 11. The photocatalytic material prepared in Example 20 is named CsPbCl3@LTA-20.

[0099] Example 21

[0100] Example 21 of this invention provides a method for preparing a photocatalytic material. The difference from Example 11 is that the heat preservation time in step S2 is changed to 90 min, while other conditions are the same as in Example 11. The photocatalytic material prepared in Example 21 is named CsPbCl3@LTA-21.

[0101] Example 22

[0102] Example 22 of this invention provides a method for preparing a photocatalytic material. The difference from Example 11 is that the holding time in step S2 is changed to 60 min, the gas introduced is Ar, and other conditions are the same as in Example 21. The photocatalytic material prepared in Example 22 is named CsPbCl3@LTA-22.

[0103] Example 23

[0104] Example 23 of this invention provides a method for preparing a photocatalytic material. The difference between this method and Example 22 is that the gas introduced in step S2 is N2, and the other conditions are the same as in Example 22. The photocatalytic material prepared in Example 23 is named CsPbCl3@LTA-23.

[0105] Example 24

[0106] Example 24 of this invention provides a method for preparing a photocatalytic material, which differs from Example 23 in that the molar ratio of PbCl2 to MnCl2 in the mixed salt in step SO is changed to 4:1, while other conditions remain the same as in Example 23. The photocatalytic material obtained in Example 24 is named CsPb. 0.8 Mn 0.2 Cl3@LTA-24.

[0107] Example 25

[0108] Example 25 of this invention provides a method for preparing a photocatalytic material, which differs from Example 23 in that the molar ratio of PbCl2 to MnCl2 in the mixed salt in step S0 is changed to 3:2, while other conditions are the same as in Example 23; the photocatalytic material obtained in Example 25 is named CsPb 0.6 Mn 0.4 Cl3@LTA-25.

[0109] Example 26

[0110] Example 26 of this invention provides a method for preparing a photocatalytic material, which differs from Example 23 in that the molar ratio of PbCl2 to MnCl2 in the mixed salt in step S0 is changed to 2:3, while other conditions are the same as in Example 23; the photocatalytic material obtained in Example 26 is named CsPb 0.4 Mn 0.6 Cl3@LTA-26.

[0111] Example 27

[0112] Example 27 of this invention provides a method for preparing a photocatalytic material, which differs from Example 23 in that the molar ratio of PbCl2 to MnCl2 in the mixed salt in step S0 is changed to 1:4, while other conditions are the same as in Example 23; the photocatalytic material obtained in Example 27 is named CsPb 0.2 Mn 0.8 Cl3@LTA-27.

[0113] Example 28

[0114] Example 28 of this invention provides a method for preparing a photocatalytic material, which differs from Example 23 in that: the molar ratio of CsCl to the mixed salt in step S0 is 2:1, the curing humidity in step S3 is 10±5%, and other conditions are the same as in Example 23; the photocatalytic material prepared in Example 28 is named CsPbCl3@LTA-28.

[0115] Example 29

[0116] Example 29 of this invention provides a method for preparing a photocatalytic material, which differs from Example 28 in that the curing humidity in step S3 is 30±5%, and other conditions are the same as in Example 28; the photocatalytic material prepared in Example 29 is named CsPbCl3@LTA-29.

[0117] Example 30

[0118] Example 30 of this invention provides a method for preparing a photocatalytic material, which differs from Example 28 in that: the curing humidity in step S3 is 90±5%, and other conditions are the same as in Example 28; the photocatalytic material prepared in Example 30 is named CsPbCl3@LTA-30.

[0119] Example 31

[0120] Example 31 of this invention provides a method for preparing a photocatalytic material, which differs from Example 28 in that: the curing humidity in step S3 is 60±5%, the curing temperature is 30℃, and other conditions are the same as in Example 28; the photocatalytic material prepared in Example 31 is named CsPbCl3@LTA-31.

[0121] Example 32

[0122] Example 32 of this invention provides a method for preparing a photocatalytic material, which differs from Example 31 in that the curing temperature in step S3 is 40°C, and other conditions are the same as in Example 31; the photocatalytic material prepared in Example 32 is named CsPbCl3@LTA-32.

[0123] Example 33

[0124] Example 33 of this invention provides a method for preparing a photocatalytic material, which differs from Example 31 in that the curing temperature in step S3 is 50°C, and other conditions are the same as in Example 31; the photocatalytic material prepared in Example 33 is named CsPbCl3@LTA-33.

[0125] Example 34

[0126] Example 34 of this invention provides a method for preparing a photocatalytic material, which differs from Example 33 in that: the curing temperature in step S3 is 20°C and the curing time is 5 days, while other conditions are the same as in Example 33; the photocatalytic material prepared in Example 33 is named CsPbCl3@LTA-33.

[0127] Example 35

[0128] Example 35 of this invention provides a method for preparing a photocatalytic material, which differs from Example 33 in that the curing time in step S3 is 10 days, and other conditions are the same as in Example 33; the photocatalytic material prepared in Example 35 is named CsPbCl3@LTA-35.

[0129] Example 36

[0130] Example 36 of this invention provides a method for preparing a photocatalytic material, which differs from Example 33 in that the curing time in step S3 is 20 days, and other conditions are the same as in Example 33; the photocatalytic material prepared in Example 36 is named CsPbCl3@LTA-36.

[0131] Comparative Example 1

[0132] Comparative Example 1 provides a CsPb 0.2 Mn 0.8 The method for preparing Cl3QDs powder is used in conjunction with CsPb in Example 27. 0.2 Mn 0.8 Stability comparison of Cl3@LTA-27 includes the following steps:

[0133] CS1. A mixture of 41.0 mg cesium carbonate, 19.0 mg lead acetate trihydrate, 34.6 mg manganese acetate, 2 mL oleic acid, 2 mL oleylamine, and 10 mL 1-octadecene was prepared in a 50 mL three-necked flask. The mixture was stirred and degassed under vacuum at room temperature for 10 min, and then argon was introduced and held for 1 min. The degaussing-introduction process was repeated three times. The mixture was then heated to 100 °C under vacuum and then heated to 120 °C under argon and held at this temperature for 40 min to obtain a clear, pale yellow solution.

[0134] CS2. Raise the temperature to 170℃ and quickly inject 0.2 mL of benzoyl chloride (1.70 mmol); after 5 s, cool the reaction mixture in an ice-water bath for 2 min to obtain solution two.

[0135] CS3. Divide the solution II obtained from CS2 into 6 centrifuge tubes, add ethyl acetate and mix thoroughly (solution II: ethyl acetate = 1:2, V / V). Centrifuge at 8000 rpm for 3 min and discard the supernatant. Disperse the precipitate in 6 mL of n-hexane by shaking, centrifuge at 3000 rpm for 3 min and discard the precipitate to obtain solution III.

[0136] CS4. Solution 3 was dried under vacuum at 80°C for 12 hours to obtain CsPb. 0.2 Mn 0.8 Cl3QDs powder is available for use.

[0137] Comparative analysis:

[0138] CsPb prepared in Examples 23-27 were obtained using a SmartLab 9KW X-ray diffractometer at 40kV and 40mA. 1-x Mn x X-ray diffraction pattern of Cl3@LTA, such as Figure 2 As shown.

[0139] CsPbCl3@LTA-23 prepared in Example 23 and CsPb prepared in Example 26 were observed under a transmission electron microscope. 0.4 Mn 0.6 Transmission electron microscopy images of Cl3@LTA-26, such as Figure 3 As shown.

[0140] CsPb obtained through Examples 23-27 1-x Mn x Cl3@LTA was used as a photocatalyst for the catalytic reduction of CO2, with CO and CH4 as the main reduction products. The experiment verified the reduction yield by detecting the concentrations of CO and CH4. The main aspects included the following:

[0141] (1) The yield of CO2 reduction catalyzed by photocatalysis is as follows: Figure 4 As shown;

[0142] (2) The photocatalyst prepared in the example with the highest reduction yield was used as the experimental object for stability verification. The stability test results are as follows: Figure 5 As shown;

[0143] (3) The photocatalyst prepared in the example with the highest reduction yield was used as the experimental object for verifying the adsorption capacity, and the results are as follows: Figure 6 As shown.

[0144] The yield results for catalytic CO2 reduction are as follows: Figure 4 As shown in Table 1:

[0145] Table 1

[0146]

[0147] The results of the catalytic performance verification of the photocatalyst for CO2 reduction are as follows: Figure 5 As shown, the data is as follows:

[0148] CsPb prepared in Example 26 0.4 Mn 0.6 After five cycles of cyclic catalytic reduction of CO2 using Cl3@LTA-26 as a catalyst, the yield remained at 53.77% of the original level.

[0149] CsPb prepared in Example 26 0.4Mn 0.6 Cl3@LTA calculates the specific surface area by measuring the N2 adsorption capacity of the photocatalytic material. The N2 adsorption capacity is as follows: Figure 6 As shown; the obtained specific surface area data are as follows:

[0150] CsPb 0.4 Mn 0.6 The specific surface area of ​​Cl3@LTA is 2.25 m². 2 / g, far higher than CsPb 0.2 Mn 0.8 Cl3QDs(0.25m 2 / g).

[0151] The effect of the curing step on the photocatalyst was verified by detecting the fluorescence intensity of the photocatalyst material prepared in Example 23. The results are as follows: Figure 7 As shown.

[0152] Experimental Analysis:

[0153] See Figure 2 Simultaneously, it is possible to observe CsPb. 1-x Mn x The diffraction peaks of Cl3QDs and LTA show that as the proportion of MnCl2 in PQDs increases, the diffraction peaks of PQDs shift at large angles, indicating lattice shrinkage and Mn... 2+ Successfully introduced into the CsPbCl3 lattice; due to the PQDs being much smaller than the LTA and being blocked by the LTA channels, CsPb 1-x Mn x The diffraction peak intensity of Cl3 QDs is weaker than that of LTA.

[0154] See Figure 3 It can be seen that PQDs are distributed on LTA.

[0155] See Figure 4 Based on the CO2 reduction data in Table 1, it can be concluded that the CsPb obtained in Example 26... 0.4 Mn 0.6 Cl3@LTA-26 was the highest yield photocatalyst for catalytic CO2 reduction.

[0156] See Figure 5 The CsPb obtained in Example 26 0.4 Mn 0.6 After five cycles of cyclic catalytic reduction of CO2 using Cl3@LTA-26 as a catalyst, the yield remained at 53.77% of the original level, demonstrating the good stability of the catalyst.

[0157] See Figure 6The CsPb prepared in Comparative Example 1 was obtained by using the N2 adsorption-desorption curves and adsorption-desorption curves of Comparative Example 1 and Example 26 through Quantachrome NovaWin. 0.2 Mn 0.8 Cl3QDs powder and CsPb prepared in Example 26 0.4 Mn 0.6 The specific surface area data of Cl3@LTA-26 showed that coating with LTA increased the surface area of ​​CsPb prepared in Example 26. 0.4 Mn 0.6 The specific surface area of ​​Cl3@LTA-26 can be used to determine that the photocatalytic material with increased specific surface area can adsorb more CO2.

[0158] See Figure 7 The photocatalytic material prepared in Example 23 showed enhanced fluorescence after curing, indicating that the amount of CsPbCl3 increased or the crystallinity was enhanced during the curing process. That is, the moisture in the air promoted the crystallization of CsPbCl3, which is a unique phenomenon that can occur in perovskite quantum dots coated with molecular sieves.

[0159] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the invention as set forth in the claims. Furthermore, the invention described herein may have other embodiments and can be implemented or carried out in various ways.

Claims

1. A method for preparing a photocatalytic material for the photocatalytic reduction of carbon dioxide to carbon monoxide and methane, characterized in that, Includes the following steps: Cesium chloride and a mixed salt are uniformly mixed at a molar ratio of (1-2):(1-3) to obtain a perovskite quantum dot precursor; wherein the mixed salt is a mixture of lead chloride and manganese chloride at a molar ratio of (1-2):(1-4); the perovskite quantum dot precursor and an LTA molecular sieve support are mixed and ground at a mass ratio of 1:(1-4) to obtain a mixture; the mixture is calcined in a non-oxidizing atmosphere within a first temperature range to obtain a photocatalytic precursor; wherein the minimum value of the first temperature range is greater than or equal to the melting point of the perovskite quantum dot precursor, and the maximum value of the first temperature range is less than the decomposition temperature of the molecular sieve support; the photocatalytic precursor is cured to obtain a photocatalytic material; the curing environment temperature is controlled at 20-50℃; the curing environment humidity is controlled at 60±5%; the curing time is 5-20 days.

2. The preparation method according to claim 1, characterized in that, When calcining the mixture in a non-oxidizing atmosphere within a first temperature range, the non-oxidizing atmosphere includes nitrogen and an inert gas.

3. The preparation method according to claim 1, characterized in that, When calcining the mixture in a non-oxidizing atmosphere within a first temperature range, the first temperature range is 500-700°C.

4. The application of a photocatalytic material prepared by the method described in any one of claims 1 to 3 in the photocatalytic reduction of carbon dioxide to carbon monoxide and methane.

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