A lead-free double perovskite microcrystal with stability and good photocatalytic performance, a preparation method and application thereof

Abstract

The present application relates to a kind of stability and good photocatalytic performance of lead-free double perovskite microcrystal and its preparation method and application, belong to the preparation technical field of perovskite microcrystal.The lead-free double perovskite microcrystal of the present application is mainly Cs4MnSb2Cl 12 Microcrystal or Cs4Mn 0.7 Cu 0.3 Sb2Cl 12 Any one in microcrystal.The lead-free double perovskite microcrystal of the present application has good photocatalytic performance, with excellent stability, high purity and other advantages, shows great application potential in photocatalysis field.In addition, the preparation method of the present application is simple, easy to operate, low in equipment requirements, low in cost, low in energy consumption, suitable for large-scale production.

Description

Technical Field

[0001] This invention belongs to the field of perovskite microcrystal preparation technology, and relates to a stable lead-free double perovskite microcrystal with good photocatalytic performance, its preparation method and application. Background Technology

[0002] The method of converting CO2 into chemical feedstocks or fuels such as CO, CH4, and CH3OH using photocatalytic materials has solved both energy shortages and environmental problems. Although significant progress has been made in current research, the development of powerful, selective, and inexpensive solar-driven photocatalysts for carbon dioxide emission reduction remains crucial.

[0003] Lead halide perovskites possess advantages such as high absorption coefficients, tunable band gaps, strong visible light trapping capabilities, and high carrier mobility, making them ideal candidate materials for photocatalysts. In recent years, lead halide perovskites have been used for photocatalytic dye degradation, hydroxymethyl oxidation, hydrogen production, organic reactions, and CO2 reduction. However, the toxicity and long-term instability of lead undoubtedly hinder the widespread application of lead halide perovskites. Therefore, lead-free lead halide perovskites have become an indispensable research direction for the next stage of development of novel optoelectronic materials and devices.

[0004] Therefore, in order to mitigate the adverse effects of lead in existing lead halide metal halide materials, the study of lead-free metal halide perovskites has attracted increasing interest from researchers. Thus, it is necessary to investigate Cs₄MnSb₂Cl 12 Synthesis methods and properties of micron-sized crystals, and the regulation of Cs4MnSb2Cl by introducing Cu element. 12 The photocatalytic reduction capability of micron-sized crystals. Summary of the Invention

[0005] In view of this, one objective of the present invention is to provide a stable lead-free double perovskite microcrystal with good photocatalytic performance; another objective of the present invention is to provide a method for preparing a stable lead-free double perovskite microcrystal with good photocatalytic performance; and a third objective of the present invention is to provide an application of a stable and high-purity lead-free double perovskite microcrystal in the photocatalytic reduction of CO2.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] 1. A stable, lead-free double perovskite microcrystal with good photocatalytic performance, wherein the lead-free double perovskite microcrystal is Cs4MnSb2Cl 12 Micron crystals or Cs4Mn 0.7 Cu 0.3 Sb2Cl 12 Any type of micron-sized crystal.

[0008] 2. The above-mentioned method for preparing lead-free double perovskite microcrystals, wherein the lead-free double perovskite microcrystals are Cs4MnSb2Cl 12 When preparing micron-sized crystals, the preparation method includes the following steps:

[0009] (1) Add antimony trioxide and manganese chloride to the hydrogen chloride solution, stir until dissolved and mixed evenly, then add cesium chloride and continue stirring until dissolved to obtain a mixed solution;

[0010] (2) Wash the mixed solution from step (1) 4-5 times with anhydrous ethanol, centrifuge at 3000-5000 rpm for 5-10 min, remove the supernatant, and place the resulting precipitate in a vacuum drying oven at 60-80℃ for 8-12 h to obtain Cs4MnSb2Cl. 12 Micron-sized crystals.

[0011] Preferably, the mass concentration of hydrogen chloride in the hydrogen chloride solution is 38%.

[0012] Preferably, the molar volume ratio of the antimony trioxide, manganese chloride, cesium chloride, and hydrogen chloride solution is 1:1:4:10, mmol:mol:mmol:mL.

[0013] 3. The above-mentioned method for preparing lead-free double perovskite microcrystals, wherein the lead-free double perovskite microcrystals are Cs4Mn 0.7 Cu 0.3 Sb2Cl 12 When micron-sized crystals are formed, the preparation method includes the following steps:

[0014] (1) Add antimony trioxide, manganese chloride and copper chloride to the hydrogen chloride solution, stir until dissolved and mixed evenly, then add cesium chloride and continue stirring until dissolved to obtain a mixed solution;

[0015] (2) Wash the mixed solution from step (1) with anhydrous ethanol 4-5 times, centrifuge at 3000-5000 rpm for 5-10 min, remove the supernatant to obtain the precipitate, place it in a vacuum drying oven and dry at 60-80℃ for 8-12 h to obtain Cs4Mn. 0.7 Cu 0.3 Sb2Cl 12 Micron-sized crystals.

[0016] Preferably, the mass concentration of hydrogen chloride in the hydrogen chloride solution is 38%.

[0017] Preferably, the molar volume ratio of the antimony trioxide, manganese chloride, copper chloride, cesium chloride and hydrogen chloride solution is 1:0.7:0.3:4:10, mmol:mmol:mmol:mmol:mL.

[0018] 3. The application of the above-mentioned lead-free double perovskite microcrystals in photocatalytic reduction of CO2.

[0019] The beneficial effects of this invention are as follows: This invention discloses a stable lead-free double perovskite microcrystal with good photocatalytic performance, mainly composed of Cs4MnSb2Cl 12 Micron crystals or Cs4Mn 0.7 Cu 0.3 Sb2Cl 12 Any type of micron-sized crystal. The lead-free double perovskite micron-sized crystals of the present invention exhibit excellent photocatalytic performance, with advantages such as superior stability and high purity, showing great application potential in the field of photocatalysis. Furthermore, the preparation method of the stable lead-free double perovskite micron-sized crystals with excellent photocatalytic performance of the present invention is simple and easy to operate, with low equipment requirements, low cost, and low energy consumption, making it suitable for large-scale production.

[0020] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0021] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0022] Figure 1 The lead-free double perovskite microcrystals (Cs4MnSb2Cl) prepared in Example 1 12 Microcrystals (a) and lead-free double perovskite microcrystals (Cs4Mn) prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 Flowchart of micron-sized crystal (b);

[0023] Figure 2 The lead-free double perovskite microcrystals (Cs4MnSb2Cl) prepared in Example 1 12 Micron-crystals) and lead-free double perovskite micron-crystals (Cs4Mn) prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 X-ray powder diffraction (XRD) pattern of micron-sized crystals;

[0024] Figure 3 The lead-free double perovskite microcrystals (Cs4MnSb2Cl) prepared in Example 1 12Microcrystals (a) and lead-free double perovskite microcrystals (Cs4Mn) prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 Scanning electron microscope (SEM) image of the micron-sized crystal (b);

[0025] Figure 4 The lead-free double perovskite microcrystals (Cs4MnSb2Cl) prepared in Example 1 12 Microcrystals (a) and lead-free double perovskite microcrystals (Cs4Mn) prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 (b) X-ray powder diffraction pattern (XRD) after high-temperature treatment and ultraviolet lamp irradiation. Detailed Implementation

[0026] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0027] Example 1

[0028] A stable, lead-free double perovskite microcrystal (Cs4MnSb2Cl) with good photocatalytic performance 12 (micron crystals), the process is as follows Figure 1 As shown in Figure a, the specific preparation method includes the following steps:

[0029] (1) Add antimony trioxide and manganese chloride to hydrogen chloride solution (the mass concentration of hydrogen chloride in the hydrogen chloride solution is 38%), stir until dissolved and mixed evenly, then add cesium chloride (where the molar volume ratio of antimony trioxide, manganese chloride, cesium chloride and hydrogen chloride solution is 1:1:4:10, mmol:mol:mmol:mL), and continue stirring until dissolved to obtain a mixed solution;

[0030] (2) Wash the mixed solution from step (1) 4-5 times with anhydrous ethanol, centrifuge at 4000 rpm for 8 min, remove the supernatant, and place the resulting precipitate in a vacuum drying oven at 70℃ for 10 h to obtain stable lead-free double perovskite microcrystals (Cs4MnSb2Cl) with good photocatalytic performance. 12 (micron crystals).

[0031] Example 2

[0032] A stable, lead-free double perovskite microcrystal (Cs4MnSb2Cl) with good photocatalytic performance 12 Micron-sized crystals are prepared using the following steps:

[0033] (1) Add antimony trioxide and manganese chloride to hydrogen chloride solution (the mass concentration of hydrogen chloride in the hydrogen chloride solution is 38%), stir until dissolved and mixed evenly, then add cesium chloride (where the molar volume ratio of antimony trioxide, manganese chloride, cesium chloride and hydrogen chloride solution is 1:1:4:10, mmol:mol:mmol:mL), and continue stirring until dissolved to obtain a mixed solution;

[0034] (2) Wash the mixed solution from step (1) 4-5 times with anhydrous ethanol, centrifuge at 3000 rpm for 10 min, remove the supernatant, and place the resulting precipitate in a vacuum drying oven at 60℃ for 12 h to obtain stable lead-free double perovskite microcrystals (Cs4MnSb2Cl) with good photocatalytic performance. 12 (micron crystals).

[0035] Example 3

[0036] A stable, lead-free double perovskite microcrystal (Cs4MnSb2Cl) with good photocatalytic performance 12 Micron-sized crystals are prepared using the following steps:

[0037] (1) Add antimony trioxide and manganese chloride to hydrogen chloride solution (the mass concentration of hydrogen chloride in the hydrogen chloride solution is 38%), stir until dissolved and mixed evenly, then add cesium chloride (where the molar volume ratio of antimony trioxide, manganese chloride, cesium chloride and hydrogen chloride solution is 1:1:4:10, mmol:mol:mmol:mL), and continue stirring until dissolved to obtain a mixed solution;

[0038] (2) Wash the mixed solution from step (1) 4-5 times with anhydrous ethanol, centrifuge at 5000 rpm for 5 min, remove the supernatant, and place the resulting precipitate in a vacuum drying oven at 80℃ for 8 h to obtain stable lead-free double perovskite microcrystals (Cs4MnSb2Cl) with good photocatalytic performance. 12 (micron crystals).

[0039] Example 4

[0040] A stable, lead-free double perovskite microcrystal (Cs4Mn) with good photocatalytic performance 0.7 Cu 0.3 Sb2Cl12 (micron crystal), the process is as follows Figure 1 As shown in Figure b, the specific preparation method includes the following steps:

[0041] (1) Add antimony trioxide, manganese chloride, and copper chloride to a hydrogen chloride solution (the mass concentration of hydrogen chloride in the hydrogen chloride solution is 38%), stir until dissolved and mixed evenly, then add cesium chloride (where the molar volume ratio of antimony trioxide, manganese chloride, copper chloride, cesium chloride and hydrogen chloride solution is 1:0.7:0.3:4:10, mmol:mmol:mmol:mmol:mL), and continue stirring until dissolved to obtain a mixed solution;

[0042] (2) Wash the mixed solution from step (1) with anhydrous ethanol 4-5 times, centrifuge at 4000 rpm for 8 min, remove the supernatant to obtain the precipitate, place it in a vacuum drying oven and dry at 70℃ for 10 h to obtain stable lead-free double perovskite microcrystals (Cs4Mn) with good photocatalytic performance. 0.7 Cu 0.3 Sb2Cl 12 (micron crystals).

[0043] Example 5

[0044] A stable, lead-free double perovskite microcrystal (Cs4Mn) with good photocatalytic performance 0.7 Cu 0.3 Sb2Cl 12 Micron-sized crystals are prepared using the following steps:

[0045] (1) Add antimony trioxide, manganese chloride, and copper chloride to a hydrogen chloride solution (the mass concentration of hydrogen chloride in the hydrogen chloride solution is 38%), stir until dissolved and mixed evenly, then add cesium chloride (where the molar volume ratio of antimony trioxide, manganese chloride, copper chloride, cesium chloride and hydrogen chloride solution is 1:0.7:0.3:4:10, mmol:mmol:mmol:mmol:mL), and continue stirring until dissolved to obtain a mixed solution;

[0046] (2) Wash the mixed solution from step (1) with anhydrous ethanol 4-5 times, centrifuge at 3000 rpm for 10 min, remove the supernatant to obtain the precipitate, place it in a vacuum drying oven and dry at 60℃ for 12 h to obtain stable lead-free double perovskite microcrystals (Cs4Mn) with good photocatalytic performance. 0.7 Cu 0.3 Sb2Cl 12 (micron crystals).

[0047] Example 6

[0048] A stable, lead-free double perovskite microcrystal (Cs4Mn) with good photocatalytic performance 0.7 Cu 0.3 Sb2Cl 12 Micron-sized crystals are prepared using the following steps:

[0049] (1) Add antimony trioxide, manganese chloride, and copper chloride to a hydrogen chloride solution (the mass concentration of hydrogen chloride in the hydrogen chloride solution is 38%), stir until dissolved and mixed evenly, then add cesium chloride (where the molar volume ratio of antimony trioxide, manganese chloride, copper chloride, cesium chloride and hydrogen chloride solution is 1:0.7:0.3:4:10, mmol:mmol:mmol:mmol:mL), and continue stirring until dissolved to obtain a mixed solution;

[0050] (2) Wash the mixed solution from step (1) with anhydrous ethanol 4-5 times, centrifuge at 5000 rpm for 5 min, remove the supernatant to obtain the precipitate, place it in a vacuum drying oven and dry at 80℃ for 8 h to obtain stable lead-free double perovskite microcrystals (Cs4Mn) with good photocatalytic performance. 0.7 Cu 0.3 Sb2Cl 12 (micron crystals).

[0051] Performance testing

[0052] Figure 2 The lead-free double perovskite microcrystals (Cs4MnSb2Cl) prepared in Example 1 12 Micron-crystals) and lead-free double perovskite micron-crystals (Cs4Mn) prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 X-ray powder diffraction (XRD) pattern of micron-sized crystals. Figure 2 It can be seen that the Cs4MnSb2Cl prepared in Example 1 12 Micron-sized crystals and Cs4Mn prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 The diffraction characteristic peaks of the micron-sized crystals were compared with those obtained from the calculated standard comparison card (Cs4MnSb2Cl). 12 The characteristic peaks of Cs4MnSb2Cl are consistent, indicating that the preparation method of the present invention can indeed successfully prepare Cs4MnSb2Cl. 12 Micron-sized crystals and Cs4Mn 0.7 Cu 0.3 Sb2Cl 12 Micron-sized crystals.

[0053] The lead-free double perovskite microcrystals (Cs4MnSb2Cl) prepared in Example 1 were used... 12)Microcrystals and lead-free double perovskite microcrystals (Cs4Mn) prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 Scanning electron microscopy (SEM) analysis was performed on the micron-sized crystal, and the results are as follows: Figure 3 As shown in a and b. From Figure 3 It can be seen that the Cs4MnSb2Cl prepared in Example 1 12 Micron-sized crystals and Cs4Mn prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 Micron-sized crystals all have a microcrystalline structure and are oblate in shape. The smaller particle size is more conducive to CO2 adsorption, thereby promoting photocatalytic performance.

[0054] The lead-free double perovskite microcrystals (Cs4MnSb2Cl) prepared in Example 1 were used... 12 Micron-crystals) and lead-free double perovskite micron-crystals (Cs4Mn) prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 Micron-sized crystals were placed in an environment of 100℃ and an environment irradiated with a 365nm ultraviolet lamp for 100 hours, respectively, and then subjected to X-ray powder diffraction tests. The results are as follows: Figure 4 As shown in a and b. From Figure 4 It can be seen that after being placed in an environment of 100℃ and irradiated with a 365nm ultraviolet lamp for 100 hours, the Cs4MnSb2Cl prepared in Example 1 showed better performance. 12 Micron-sized crystals and Cs4Mn prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 The diffraction characteristic peaks of the micron-sized crystal did not change, indicating that Cs4MnSb2Cl 12 Micron-sized crystals and Cs4Mn 0.7 Cu 0.3 Sb2Cl 12 Micron-sized crystals exhibit excellent stability.

[0055] The lead-free double perovskite microcrystals (Cs4MnSb2Cl) prepared in Example 1 were used. 12 Micron-sized crystals) and lead-free double perovskite micron-sized crystals (Cs4Mn) prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 Micron-sized crystals were irradiated under a 300W Xe lamp for 3 hours and then used for the catalytic reduction of CO2. The results were as follows: The lead-free double perovskite micron-sized crystals (Cs4MnSb2Cl) prepared in Example 1 were as follows: 12The CO and CH4 yields of the micron-sized crystals were 240.201 μmol g. -1 and 58.585 μmol g -1 In Example 4, lead-free double perovskite microcrystals (Cs4Mn) were prepared. 0.7 Cu 0.3 Sb2Cl 12 The CO and CH4 yields of the micron-sized crystals were 503.86 μmol g. -1 and 68.35 μmol g -1 This demonstrates that the lead-free double perovskite microcrystals (Cs4MnSb2Cl) prepared in Example 1... 12 Micron-sized crystals) and lead-free double perovskite micron-sized crystals (Cs4Mn) prepared in Example 4 0.7 Cu 0.3 Sb2Cl 12 Micron-sized crystals can all catalyze the reduction of CO2, and Cs4MnSb2Cl 12 The addition of Cu to micron-sized crystals forms Cs4Mn. 0.7 Cu 0.3 Sb2Cl 12 Micronized crystals can significantly enhance Cs4MnSb2Cl 12 Photocatalytic performance of micron-sized crystals.

[0056] In summary, this invention discloses a stable lead-free double perovskite microcrystal with good photocatalytic performance, mainly composed of Cs4MnSb2Cl. 12 Micron crystals or Cs4Mn 0.7 Cu 0.3 Sb2Cl 12 Any type of micron-sized crystal. The lead-free double perovskite micron-sized crystals of the present invention exhibit excellent photocatalytic performance, with advantages such as superior stability and high purity, showing great application potential in the field of photocatalysis. Furthermore, the preparation method of the stable lead-free double perovskite micron-sized crystals with excellent photocatalytic performance of the present invention is simple and easy to operate, with low equipment requirements, low cost, and low energy consumption, making it suitable for large-scale production.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. The application of a lead-free double perovskite microcrystal in the photocatalytic reduction of CO2, characterized in that, The lead-free double perovskite microcrystals are Cs4Mn. 0.7 Cu 0.3 Sb2Cl 12 Micron-sized crystals.

2. The application of the lead-free double perovskite microcrystals described in claim 1 in the photocatalytic reduction of CO2, characterized in that, The preparation method of the lead-free double perovskite microcrystals includes the following steps: (1) Add antimony trioxide, manganese chloride and copper chloride to hydrogen chloride solution, stir until dissolved and mixed evenly, then add cesium chloride and continue stirring until dissolved to obtain a mixed solution; (2) Wash the mixed solution in step (1) with anhydrous ethanol 4-5 times, centrifuge at 3000-5000 rpm for 5-10 min, remove the supernatant to obtain the precipitate, place it in a vacuum drying oven and dry at 60-80℃ for 8-12 h to obtain Cs4Mn. 0.7 Cu 0.3 Sb2Cl 12 Micron-sized crystals.

3. The application of the lead-free double perovskite microcrystals according to claim 2 in the photocatalytic reduction of CO2, characterized in that, The mass concentration of hydrogen chloride in the hydrogen chloride solution is 38%.

4. The application of the lead-free double perovskite microcrystals according to claim 2 in the photocatalytic reduction of CO2, characterized in that, The molar volume ratio of the antimony trioxide, manganese chloride, copper chloride, cesium chloride and hydrogen chloride solution is 1:0.7:0.3:4:10, mmol:mmol:mmol:mmol:mL.

Images