Method for preparing high-purity cesium-based perovskite powder

Abstract

The present invention relates to a method for preparing cesium-based perovskite and, more specifically, to a method for synthesizing cesium-based perovskite with high yield and high purity, and to the cesium-based perovskite prepared by using the method.

Description

Method for manufacturing high-purity cesium-based perovskite powder

[0001] The present invention relates to a method for producing a cesium-based perovskite powder with high purity and a high-purity cesium-based perovskite produced by the method.

[0002] To address the depletion of fossil fuels and the global environmental problems caused by their use, research is actively being conducted on renewable and clean alternative energy sources such as solar energy, wind power, and hydropower.

[0003] Among these, interest in solar cells, which directly convert sunlight into electrical energy, is growing significantly. Here, a solar cell refers to a cell that generates current and voltage by utilizing the photovoltaic effect, which generates electrons and holes by absorbing light energy from sunlight.

[0004] Currently, it is possible to manufacture np diode-type silicon (Si) single crystal-based solar cells with a light energy conversion efficiency of over 20%, and these are actually being used for solar power generation. There are also solar cells using compound semiconductors such as gallium arsenide (GaAs) with even better conversion efficiencies. However, these inorganic semiconductor-based solar cells require highly purified materials to achieve high efficiency, so a lot of energy is consumed in refining the raw materials. In addition, expensive processing equipment is required in the process of forming single crystals or thin films using the raw materials, which limits the cost of lowering the manufacturing cost of solar cells, and this has been an obstacle to large-scale utilization.

[0005] Accordingly, in order to manufacture solar cells at low cost, it is necessary to drastically reduce the cost of materials or manufacturing processes used as core components of solar cells, and research is being conducted on perovskite solar cells that can be manufactured using low-cost materials and processes as an alternative to inorganic semiconductor-based solar cells.

[0006] The general structural formula of the perovskite structure is the ABX3 structure, where an anion is located at the X site, a large cation is located at the A site, and a small cation is located at the B site.

[0007] To tune the bandgap of FAPbI3-based perovskite materials to suit silicon tandem cells, the incorporation of CsPbBr3 is essential. The addition of wide-bandgap CsPbBr3 (~3.82 eV) to the narrower FAPbI3 (~1.48 eV) enables tuning to a perovskite material (~1.66 eV) suitable for tandem cells. CsPbBr3 is widely used due to its higher solubility and ease of preparation. However, Oxford PV holds a prior patent on the production of perovskites under the above conditions. Therefore, a method for tuning perovskites other than the above method is needed.

[0008] In general, there is a method to tune the A site and the halide X site to control the band gap of perovskite. In the case of the A site, it is controlled through MA (methylammonium), FA (formamdinium), Cs (cesium), etc., and research and attempts are being made to introduce cesium-based perovskites such as CsPbBr3 to FAPbI3, which is based on FA with high efficiency and high stability, and to develop modified products.

[0009] As an inorganic metal halide material, perovskite with the structure CsPbX3 (X = Cl, Br, or I) has a wide spectrum of approximately 410–700 nm, and has the advantage of being able to absorb the entire visible range and exhibit various fluorescent colors by adjusting the constituent elements. Therefore, it is very promising as a variety of optoelectronic devices such as lasers, displays, solar cells, and photosensors.

[0010] The present invention aims to provide a method for producing cesium-based perovskite with high purity and high reproducibility by optimizing the chemical composition of a precursor used in producing cesium-based perovskite, and a cesium-based perovskite produced thereby.

[0011] In order to solve the above-described problem, the present invention provides a method for producing a cesium-based perovskite, comprising the steps of: a first step of dissolving a cesium halogen compound represented by the chemical formula 1 in water to produce a first precursor aqueous solution and a second step of dissolving a lead halogen compound represented by the chemical formula 2 in an organic solvent to produce a second precursor solution; a second step of adding the first precursor aqueous solution to the second precursor solution and reacting the first precursor solution to obtain a precipitate as a reaction product; and a third step of purifying and drying the obtained precipitate to obtain a cesium-based perovskite represented by the chemical formula 3 below.

[0012] [Chemical Formula 1]

[0013] CsX (1-a) X' a

[0014] [Chemical Formula 2]

[0015] PbX (3-a)

[0016] [Chemical Formula 3]

[0017] CsPbX (3-a) X' a

[0018] In chemical formulas 1 to 3, a is 0 <a≤1을 만족하는 유리수이며, X 및 X'는 독립적으로 -Cl 또는 -Br이다.

[0019] As a preferred embodiment of the present invention, the organic solvent of step 1 may include at least one selected from among DMF (dimethylformamide), DMSO (dimethylsulfoxide), DMAc (dimethylacetamide), DMI (dimethyl imidazolidinone), GBL (gamma butyrolactone), and 2Me (2-methoxyethanol).

[0020] As a preferred embodiment of the present invention, the second precursor solution in step 1 may have a lead halide compound concentration of 0.005 M to 1.00 M.

[0021] As a preferred embodiment of the present invention, the first precursor aqueous solution in step 1 may have a cesium halogen compound concentration of 1.0 M or more.

[0022] As a preferred embodiment of the present invention, in the second step, the first precursor in the first precursor aqueous solution and the second precursor in the second precursor solution can be mixed and reacted in a molar ratio of 1:0.8 to 1.0.

[0023] As a preferred embodiment of the present invention, the second step reaction can be carried out at 15 to 35°C and under atmospheric pressure.

[0024] As a preferred embodiment of the present invention, the cesium-based perovskite obtained in step 3 may have a yield of 75.0% to 99.5% and a purity of 99.00% or more.

[0025] Another object of the present invention is a high-purity cesium-based perovskite powder, which is manufactured by the method described above and can have a purity of 99.00% or more.

[0026] Another object of the present invention relates to a perovskite composite, which is a perovskite composite using a cesium-based perovskite manufactured by the method described above, and the perovskite composite may be a perovskite represented by the following chemical formula 4.

[0027] [Chemical Formula 4]

[0028] Cs a MX b X' (3-b)

[0029] In chemical formula 4, M is a divalent cation and includes one or two selected from Fe, Co, Ni, Cu, Sn, Pb, Bi, Ge, Ti, Eu and Zr, X and X' are independently Cl, Br or I (provided that X and X' are different halogen elements), and a is 0. <a≤1의 정수이고, b는 0<a≤3의 정수이다.

[0030] In addition, another object of the present invention is to provide a perovskite solar cell including the perovskite composite as a light-absorbing layer (or photoactive layer).

[0031] The method for producing a cesium-based perovskite of the present invention can produce a high-purity cesium-based perovskite with high reproducibility and a high yield, thereby providing a cesium-based perovskite with excellent economic feasibility.

[0032] Figures 1a and 1b are photographs of cesium-based perovskites manufactured in Examples 1 to 5.

[0033] Figure 2 is a photograph taken in Comparative Example 1 of the first precursor solution (A), the second precursor solution (B), and after mixing and reacting them (C).

[0034] Figure 3 is a photograph taken in Comparative Example 2 of the first precursor solution (A), the second precursor solution (B), and after mixing and reacting them (C).

[0035] Figures 4a and 4b are XRD (X-ray diffraction) measurement data of cesium-based perovskites manufactured in Examples 1 to 5.

[0036] Figures 5a and 5b are TGA (thermal gravimetric analysis) measurement data of cesium-based perovskites manufactured in Examples 1 to 5.

[0037]

[0038] Hereinafter, the present invention will be described in more detail.

[0039] The present invention is a method for manufacturing a high-purity cesium-based perovskite having a purity of 99.00% or more with a high yield, and can be manufactured by performing the following process.

[0040] The cesium-based perovskite powder of the present invention is produced by a process comprising: a first step of dissolving a cesium halogen compound represented by Chemical Formula 1 in water to prepare a first precursor aqueous solution and a second precursor solution of dissolving a lead halogen compound represented by Chemical Formula 2 in an organic solvent; a second step of adding the first precursor aqueous solution to the second precursor solution and reacting it to obtain a precipitate as a reaction product; and a third step of purifying and drying the obtained precipitate to obtain a cesium-based perovskite represented by Chemical Formula 3.

[0041] [Chemical Formula 1]

[0042] CsX (1-a) X' a

[0043] [Chemical Formula 2]

[0044] PbX (3-a)

[0045] [Chemical Formula 3]

[0046] CsPbX (3-a) X' a

[0047] In chemical formulas 1 to 3, a is 0 <a≤1을 만족하는 유리수이며, 바람직하게는 0.30<a≤1을 만족하는 유리수이고, 더욱 바람직하게는 0.40 <a≤1을 만족하는 유리수이다. 그리고, X 및 X'는 서로 같거나 다른 할로겐으로서, 독립적으로 -Cl 또는 -Br이다.

[0048] The organic solvent used in the preparation of the second precursor solution in step 1 may include at least one selected from among DMF (dimethylformamide), DMSO (dimethylsulfoxide), DMAc (dimethylacetamide), DMI (dimethyl imidazolidinone), GBL (gamma butyrolactone), and 2Me (2-methoxyethanol), preferably at least one selected from among DMF, DMSO, DMI, and 2Me, and more preferably at least one selected from among DMF, DMSO, and DMI.

[0049] In addition, the second precursor solution may have a lead halide compound concentration of 0.005 M to 1.000 M, preferably 0.005 to 0.600 M, and more preferably 0.010 to 0.200 M. At this time, if the lead halide compound concentration is less than 0.02 M, the yield and purity of the final reaction product, cesium-based perovskite, may be low, and if it exceeds 1.0 M, there may be a problem of reaching the solubility limit.

[0050] In addition, to be more specific, when X in Chemical Formula 2 is -Cl, the concentration of the lead halide compound in the second precursor solution may be 0.005 to 0.050 M, preferably 0.010 to 0.030 M. And, when X in Chemical Formula 1 is -Br, the concentration of the lead halide compound in the second precursor solution may be 0.02 to 0.60 M, preferably 0.02 to 0.20 M.

[0051] In addition, the first precursor aqueous solution may have a cesium halogen compound concentration of 1.0 M or more, preferably 1.0 to 2.0 M, and more preferably 1.0 to 1.5 M. At this time, since water, which is a solvent of the first precursor aqueous solution, also serves as an antisolvent of the final reaction product, it is advantageous for the cesium halogen compound concentration to satisfy the above range for the synthesis of high-purity cesium-based perovskite, and if the cesium halogen compound concentration in the first precursor aqueous solution exceeds 2.0 M, the yield and purity of the cesium-based perovskite, which is the final reaction product, may be low.

[0052] In addition, to be more specific, when X in Chemical Formula 1 is -Br, the concentration of the cesium halogen compound in the first precursor aqueous solution may be 1.00 to 2.00 M, preferably 1.00 to 1.50 M. And, when X in Chemical Formula 1 is -Cl, the concentration of the cesium halogen compound in the first precursor solution may be 1.00 to 1.80 M, preferably 1.00 to 1.60 M.

[0053] Next, the second step is a process for synthesizing a precipitate as a reaction product by mixing and reacting the second precursor solution and the first precursor aqueous solution. In the second step, the first precursor in the first precursor aqueous solution and the second precursor in the second precursor solution can be mixed and reacted at a molar ratio of 1:0.8 to 1.0, preferably 1:0.9 to 1.0. At this time, if the molar ratio of the second precursor to the first precursor is less than 0.8 or exceeds 1.0, the purity of the final reaction product, cesium-based perovskite, may be lowered due to unreacted impurities, so it is preferable to perform mixing and reaction at the above ratio.

[0054] And, the second step can be carried out under ambient conditions at 15 to 35°C.

[0055] And, in the second step, after the reaction is completed, filtering can be performed to obtain the precipitate, which is the reaction product.

[0056] In addition, the three-step purification can be performed using a general method used in the art, and for example, in a preferred embodiment, the precipitate obtained through filtering is purified 3 to 4 times with a ketone solution such as acetone, dimethyl ketone, or propanone, and then filtered again to obtain a powder.

[0057] And, the powder obtained by purification can be dried using a general drying method such as thermal drying to produce a cesium-based perovskite.

[0058] And, the cesium-based perovskite obtained in the above step 3 has a yield of 70.0% or more and a purity of 98.00% or more, preferably a yield of 75.0% to 99.5% and a purity of 99.00% or more, and more preferably a yield of 75.8% to 99.0% and a purity of 99.00% to 99.90%.

[0059] Hereinafter, the present invention will be described in more detail through examples, but the following examples do not limit the scope of the present invention, and should be interpreted as helping to understand the present invention.

[0060] [Example]

[0061] Example 1: Preparation of cesium-based perovskite powder

[0062] A first precursor aqueous solution with a concentration of 1.30 M was prepared by dissolving CsBr powder (5.78 g), a cesium halide compound, in ultrapure water (DI water).

[0063] A lead halide compound powder (10.03 g), which is a compound represented by the following chemical formula 2-1, was dissolved in DMF to prepare a second precursor solution having a concentration of 0.27 M.

[0064] [Chemical Formula 2-1]

[0065] PbX (3-a)

[0066] In chemical formula 2-1, X is -Br and a is 1.

[0067] Next, while slowly stirring the second precursor solution at 22-23°C and atmospheric pressure, the first precursor aqueous solution was added dropwise to the second precursor solution, and the reaction was performed while stirring for an additional 2 hours. After allowing to stand to form a precipitate, it was filtered to obtain an orange precipitate. At this time, the reaction molar ratio of the first precursor and the second precursor was 1:1.

[0068] Next, the obtained precipitate was purified three times with acetone, filtered again to obtain a powder, and then placed in a thermal drying oven for a drying process to obtain 13.32 g of a cesium-based perovskite powder represented by the following chemical formula 3-1. A photograph of the obtained powder is shown in Fig. 1a.

[0069] And, the yield and purity of the synthesized cesium-based perovskite powder are shown in Table 3.

[0070] [Chemical Formula 3-1]

[0071] CsPb X (3-a) (X') a

[0072] In chemical formula 3-1, a is 1, and X and X' are -Br.

[0073]

[0074] Example 2: Preparation of cesium-based perovskite powder

[0075] A first precursor aqueous solution with a concentration of 1.48 M was prepared by dissolving 5.0 g of CsCl powder in ultrapure water (DI water).

[0076] A lead halide compound powder (11 g), which is a compound represented by the following chemical formula 2-1, was dissolved in DMF to prepare a second precursor solution having a concentration of 0.27 M.

[0077] [Chemical Formula 2-1]

[0078] PbX (3-a)

[0079] In chemical formula 2-1, X is -Br and a is 1.

[0080] Next, while slowly stirring the second precursor solution at 22-23°C and atmospheric pressure, the first precursor aqueous solution was added dropwise to the second precursor solution, and the reaction was performed while stirring for an additional 2 hours. After allowing to stand to form a precipitate, it was filtered to obtain a yellow precipitate. At this time, the reaction molar ratio of the first precursor and the second precursor was 1:1.

[0081] Next, the obtained precipitate was purified three times with acetone, filtered again to obtain a powder, and then placed in a thermal drying oven for a drying process to obtain 13.01 g of a cesium-based perovskite powder represented by the following chemical formula 3-2. A photograph of the obtained powder is shown in Fig. 1a.

[0082] And, the yield and purity of the synthesized cesium-based perovskite powder are shown in Table 3.

[0083] [Chemical Formula 3-2]

[0084] CsPb X (3-a) (X') a

[0085] In chemical formula 3-2, a is 1, X is -Br, and X' is -Cl.

[0086]

[0087] Example 3: Preparation of cesium-based perovskite powder

[0088] A first precursor aqueous solution with a concentration of 1.4 M was prepared by dissolving 3.0 g of CsBr powder in ultrapure water (DI water).

[0089] A lead halide compound powder (3.98 g), which is a compound represented by the following chemical formula 2-2, was dissolved in DMF to prepare a second precursor solution having a concentration of 0.02 M.

[0090] [Chemical Formula 2-2]

[0091] PbX(3-a)

[0092] In chemical formula 2-2, X is -Cl and a is 1.

[0093] Next, the first precursor aqueous solution was added to the second precursor solution, and the reaction was performed by stirring for 2 hours at 22-23°C and atmospheric pressure, followed by allowing to stand to form a precipitate, which was then filtered to obtain a light yellow precipitate. At this time, the reaction molar ratio of the first precursor and the second precursor was 1:1.

[0094] Next, the obtained precipitate was purified three times with acetone, filtered again to obtain a powder, and then placed in a thermal drying oven for a drying process to obtain 5.31 g of a cesium-based perovskite powder represented by the following chemical formula 3-3. A photograph of the obtained powder is shown in Fig. 1a.

[0095] And, the yield and purity of the synthesized cesium-based perovskite powder are shown in Table 3.

[0096] [Chemical Formula 3-3]

[0097] CsPb X (3-a) (X') a

[0098] In chemical formula 3-3, a is 2, X is -Br, and X' is -Cl.

[0099]

[0100] Example 4: Preparation of cesium-based perovskite powder

[0101] A first precursor aqueous solution with a concentration of 1.57 M was prepared by dissolving 7.95 g of CsCl powder in ultrapure water (DI water).

[0102] A lead halide compound powder (13.13 g), which is a compound represented by the following chemical formula 1-3, was dissolved in DMF to prepare a second precursor solution having a concentration of 0.02 M.

[0103] [Chemical Formula 1-3]

[0104] PbX (3-a)

[0105] In Chemical Formula 1-3, X is -Cl and a is 1.

[0106] Next, the first precursor aqueous solution was added to the second precursor solution, and the reaction was performed by stirring for 2 hours at 22-23°C and atmospheric pressure, followed by allowing to stand to form a precipitate, which was then filtered to obtain a white precipitate. At this time, the reaction molar ratio of the first precursor and the second precursor was 1:1.

[0107] Next, the obtained precipitate was purified three times with acetone, filtered again to obtain a powder, and then placed in a thermal drying oven for a drying process to obtain 20.70 g of a cesium-based perovskite powder represented by the following chemical formula 3-4. A photograph of the obtained powder is shown in Fig. 1a.

[0108] And, the yield and purity of the synthesized cesium-based perovskite powder are shown in Table 3.

[0109] [Chemical Formula 3-4]

[0110] CsPb X (3-a) (X') a

[0111] In chemical formula 3-4, a is 1, X is -Cl, and X' is -Cl.

[0112]

[0113] Example 5: Preparation of cesium-based perovskite powder

[0114] 13.8 g of CsBr powder of Preparation Example 1 used in Example 1 and 8.4 g of CsCl powder of Preparation Example 2 used in Example 2 were dissolved in ultrapure water (DI water) to prepare a first precursor aqueous solution having a concentration of 1.3 M.

[0115] In the same manner as Example 1, 3.6 g of lead halide compound powder, which is a compound represented by the above chemical formula 1-1, was dissolved in DMF to prepare a second precursor solution having a concentration of 0.27 M.

[0116] Next, the first precursor aqueous solution was added to the second precursor solution, and the reaction was performed by stirring for 2 hours at 22-23°C and atmospheric pressure, followed by allowing to stand to form a precipitate, which was then filtered to obtain a dark yellow precipitate. At this time, the reaction molar ratio of the first precursor and the second precursor was 1:1.

[0117] Next, the obtained precipitate was purified three times with acetone, filtered again to obtain a powder, and then placed in a thermal drying oven for a drying process to obtain 3.0249 g of a cesium-based perovskite powder represented by the following chemical formula 3-5. A photograph of the obtained powder is shown in Fig. 1b.

[0118] And, the yield and purity of the synthesized cesium-based perovskite powder are shown in Table 1.

[0119] [Chemical Formula 3-5]

[0120] CsPb X (3-a) (X') a

[0121] In chemical formula 3-5, a is 0.5, X is -Br, and X' is -Cl.

[0122] Classification First precursor concentration in aqueous solution Second precursor concentration in aqueous solution Perovskite yield Purity Example 11.30 M0.27 MCsPbBr 3 84.0% 99% Example 21.48 M0.27 MCsPbBr 2 Cl 8 1.0% 99% Example 31.40 M0.02 MCsPbCl 2 Br 7 6.0% 99% Example 41.57 M0.02 MCsPbCl 3 98.0% 99% Example 51.30 M0.27 MCsPbBr 2.5 Cl 0.5 86.0%99%

[0123]

[0124] Comparative Example 1

[0125] CsBr powder (5.78 g) was dissolved in DMF to prepare a first precursor solution with a concentration of 1.30 M (see A in Fig. 2).

[0126] A lead halide compound powder (10.03 g), which is a compound represented by the following chemical formula 2-1, was dissolved in DMF to prepare a second precursor solution having a concentration of 0.27 M (see B in Fig. 2).

[0127] [Chemical Formula 2-1]

[0128] PbX (3-a)

[0129] In chemical formula 2-1, X is -Br and a is 1.

[0130] Next, the first precursor aqueous solution was added dropwise to the second precursor solution while slowly stirring the second precursor solution at 22-23°C and atmospheric pressure, and then stirred for an additional 2 hours. Even after stirring for an additional 1 hour, no reaction occurred (see C in Fig. 2).

[0131] This is the result of only the solvent (DMF) being present in the first and second precursor mixture solution and no antisolvent being present, so no reaction occurred.

[0132]

[0133] Comparative Example 2

[0134] CsBr powder (5.78 g) was dissolved in ultrapure water (DI water) to prepare a first precursor aqueous solution with a concentration of 1.30 M (see A in Fig. 3).

[0135] When the lead halide compound powder (10.03 g), which is a compound represented by the following chemical formula 2-1, was added to ultrapure water (DI water) and stirred, the lead halide compound powder did not dissolve in the water (see B in Fig. 3), and no reaction occurred even when the first precursor aqueous solution was added dropwise thereto (see C in Fig. 3).

[0136]

[0137] Experimental example: XRD and TGA measurements

[0138] XRD and TGA were measured for each of the cesium-based perovskite powders manufactured in Examples 1 to 5, and the results are shown in Fig. 4a (Examples 1 to 4), Fig. 4b (Example 5), Fig. 5a (Examples 1 to 4), and Fig. 5b (Example 5).

[0139] Looking at the XRD measurement results of Figs. 4a and 4b, it can be seen that as Br is replaced with Cl, the XRD position gradually moves to a higher angle around 21°. This is because the lattice constant decreases as the amount of Cl, which is smaller than Br, increases.

[0140] In addition, looking at the TGA measurement results of FIGS. 5a and 5b, no weight loss is observed except in section 1 (weight loss from around 600°C), which means that the materials are well bonded and nothing other than a single substance exists. In addition, it was confirmed that the weight loss section gradually shifts to higher temperatures as the Cl content increases.

[0141]

[0142] Example 6 and Comparative Examples 3 to 5

[0143] A perovskite compound represented by CsPbBr2Cl was prepared in the same manner as in Example 2, but the concentration of the first precursor in the first precursor aqueous solution or the concentration of the second precursor in the second precursor aqueous solution was changed as shown in Table 4 below, and Examples 6 to 7 and Comparative Examples 2 to 3 were performed, respectively. The yield and purity of the synthesized perovskite compound are shown in Table 2.

[0144] Classification First precursor concentration in aqueous solution Second precursor concentration in aqueous solution Perovskite yield Purity Example 21.48 M0.27 MCsPbBr2Cl 81.0% 99.6% Example 61.05 M0.27 MCsPbBr2Cl 74.2% 99.2% Comparative example 32.60 M0.27 MCsPbBr2Cl 34.2% 97.6% Comparative example 40.85 M0.20 MCsPbBr2Cl 64.2% 98.2% Comparative example 50.75 M0.10 MCsPbBr2Cl 37.1% 97.8%

[0145] Looking at Table 2 above, Examples 2 and 6 showed results that satisfied both a high yield of 70% or more and a high purity of 95% or more. In contrast, in Comparative Example 3, where the concentration of the first precursor aqueous solution exceeded 2.00 M, the concentration of the first precursor aqueous solution became too high, resulting in a relatively insufficient amount of anti-solvent, which resulted in a problem of a significantly low yield. In addition, reaction products such as PbBr3 were generated and precipitated, resulting in a problem of low yield as well as purity. In addition, in Comparative Examples 4 and 5, where the concentration of the first precursor aqueous solution was less than 1.00 M, although the purity was high, there was a problem of poor yield overall. It is believed that this is because the final product is dissolved in DMF, which is a solvent of the second precursor solution.

[0146]

[0147] Through the above examples and experimental examples, it was confirmed that high-purity cesium-based perovskite can be manufactured in high yield.

Claims

1. Step 1: Dissolving a cesium halogen compound represented by chemical formula 1 in water to prepare a first precursor aqueous solution, and dissolving a lead halogen compound represented by chemical formula 2 in an organic solvent to prepare a second precursor solution; Step 2: adding and reacting the first precursor solution to the second precursor solution to obtain a precipitate as a reaction product; and A method for producing a cesium-based perovskite, characterized by performing a process including the step of purifying and drying the obtained precipitate to obtain a cesium-based perovskite represented by the following chemical formula 3; [Chemical Formula 1] CsX (1-a) X' a [Chemical formula 2] PbX (3-a) [Chemical Formula 3] CsPbX (3-a) X' a In chemical formulas 1 to 3, a is 0 <a≤1을 만족하는 유리수이며, X 및 X'는 독립적으로 -Cl 또는 -Br이다.

2. A method for producing a cesium-based perovskite, characterized in that in the first paragraph, the organic solvent of step 1 includes at least one selected from DMF (dimethylformamide), DMSO (dimethylsulfoxide), DMAc (dimethylacetamide), DMI (dimethyl imidazolidinone), GBL (gamma butyrolactone), and 2Me (2-methoxyethanol).

3. A method for producing a cesium-based perovskite according to claim 1, wherein the second precursor solution has a lead halogen compound concentration of 0.005 M to 1,000 M.

4. A method for producing a cesium-based perovskite, characterized in that the first precursor aqueous solution has a cesium halogen compound concentration of 1.0 M or more in the first paragraph.

5. A method for producing a cesium-based perovskite, characterized in that in the first paragraph, the second step comprises mixing and reacting the first precursor in the first precursor aqueous solution and the second precursor in the second precursor solution at a molar ratio of 1:0.8 to 1.

0.

6. A method for producing a cesium-based perovskite, characterized in that the second step reaction in paragraph 1 is performed at 20 to 35°C and under atmospheric pressure.

7. A method for producing a cesium-based perovskite, characterized in that the cesium-based perovskite obtained in step 3 in paragraph 1 has a yield of 75.0% to 99.5% and a purity of 99.00% or higher.

8. A cesium-based perovskite powder manufactured by one of the methods selected from clauses 1 to 7, characterized in that the cesium-based perovskite has a purity of 99.00% or higher.

9. A perovskite complex manufactured using the cesium-based perovskite of Article 8, characterized in that it is a perovskite represented by the following chemical formula 4; [Chemical Formula 4] Cs a MX b X' (3-b) In chemical formula 4, M is a divalent cation, including one or two selected from Fe, Co, Ni, Cu, Sn, Pb, Bi, Ge, Ti, Eu and Zr, X and X' are independently Cl, Br or I (provided that X and X' are different halogen elements), and a is 0. <a≤1의 정수이고, b는 0<a≤3의 정수이다.

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