TWI814965B - Perovskite precursor solution and manufacturing method of perovskite light-absorbing layer - Google Patents

Abstract

The disclosure provides a perovskite precursor solution, including: a plurality of halides, AX and BX₂ to form a perovskite with a chemical formula of ABX_3, a first solvent, and a second solvent, wherein A is a monovalent cation and B is two valence cation, X is a halogen ion, and the first solvent includes dimethylformamide (DMF), dimethylsulfinium (DMSO), γ-butyrolactone (GBL), N-methylpyrrolidone (NMP), acetonitrile (ACN), or a combination thereof, the second solvent includes chlorobenzene (Ethanol), isopropyl alcohol (IPA), toluene, ethyl acetate (EA), dimethyl carbonate (DMC), dicarbonate Ethyl ester (DC) or a combination thereof, and the volume ratio of the first solvent to the second solvent is between 1: 0.01 and 1: 0.2. This disclosure also provides perovskite solar cell manufacturing methods and perovskite solar cells.

Description

Perovskite precursor solution and method for manufacturing perovskite absorption layer

The present invention relates to a perovskite precursor solution, and more particularly to a precursor solution for preparing a perovskite absorption layer for high-efficiency solar cells.

Today, with the exhaustion of fossil energy and worsening environmental problems, solar energy sources are inexhaustible and have gradually become a market for competing investments. Traditional silicon-based solar cells have serious limitations on their development due to their high cost and large energy consumption. Perovskite solar cells have become a research topic due to their full range response in the visible light region, good photogenerated carrier transmission and cheap and abundant raw materials. focus.

In recent years, the photoelectric conversion efficiency of perovskite solar cells has rapidly exceeded 20%, and the current highest efficiency in the world has reached 24.2% (KRICT, 2019). In addition, perovskite has adjustable energy gap, high absorption coefficient, and excellent carrier generation and separation capabilities. In the future, it will also have the opportunity to be promoted to perovskite-related application technologies, such as: perovskite light-emitting diodes, Perovskite laser, perovskite field effect transistor.

However, factors such as the microstructure, grain size, grain boundaries, hole density, crystal quality, and preferred direction of crystallization of the perovskite absorber layer will significantly affect the performance of the solar cell, and during the perovskite preparation process, the film layer must be uniform The regulation of properties and thin film microstructure has a huge impact on the efficiency of solar cells. Therefore, a perovskite preparation method is urgently needed to provide a perovskite absorption layer with good photoelectric conversion efficiency.

Figures 1A to 1C are scanning electron microscope (SEM) photos of Examples and Comparative Examples.

Figure 2 shows the X-ray diffraction analysis (XRD) patterns of the examples and comparative examples.

Figure 3 shows the photoluminescence (PL) spectra of Examples and Comparative Examples.

Figure 4 shows the time-resolved photofluorescence (TRPL) spectra of Examples and Comparative Examples.

The present disclosure provides a perovskite precursor solution, including a plurality of halides, AX and BX ₂ , to form a perovskite with a chemical formula of ABX ₃ ; a first solvent; where A is a monovalent cation and B is a divalent cation, Where NMP), acetonitrile (ACN), or a combination of the above, the second solvent includes chlorobenzene (CB), water, ethanol (Ethanol), iso-propanol (IPA), toluene (Toluene), ethyl acetate Ethyl Acetate (EA), dimethyl carbonate (DMC), diethyl carbonate (DC), or a combination of the above, and the volume ratio of the first solvent to the second solvent is between 1:0.01 and 1: between 0.2.

The disclosure also provides a method for manufacturing a perovskite absorption layer, which includes: providing a substrate; adding a perovskite precursor solution on the substrate; spin-coating the perovskite precursor solution for the first time on the substrate. forming a perovskite film; then spin-coating the substrate carrying the perovskite film for a second time, and adding an antisolvent to the perovskite film; and annealing the substrate carrying the perovskite film to form a perovskite film Mineral absorption layer, wherein the perovskite precursor solution includes: a plurality of halides, AX and BX ₂ to form a perovskite with a chemical formula of ABX ₃ ; a first solvent; a second solvent; and wherein A is a monovalent cation , B is a divalent cation, and combination, the second solvent includes chlorobenzene, ethanol, isopropyl alcohol, toluene, ethyl acetate, dimethyl carbonate, diethyl carbonate, or a combination of the foregoing, and the volume ratio of the first solvent to the second solvent Between 1:0.01 and 1:0.20.

The disclosure further provides a perovskite solar cell, including a substrate with a conductive layer; an electron transport layer disposed on the substrate; a perovskite absorption layer disposed on the electron transport layer; and a hole transport layer disposed on the perovskite The absorption layer and the electrode layer are arranged on the hole transport layer, in which the diffraction peak intensity ratio of the XRD pattern of the perovskite absorption layer in the (220) crystallization direction and the (310) crystallization direction is between 0.9 and 1.1. .

An embodiment of the present disclosure provides a method for forming a perovskite absorption layer, including: providing a substrate, and adding a perovskite precursor solution including a plurality of halides, a first solvent, and a second solvent on the glass substrate. In one embodiment, the substrate may be any suitable substrate, such as a glass substrate, a flexible substrate or a polymer substrate, or may be a transparent or opaque rigid or flexible substrate, but is not limited thereto. The plurality of halides include AX and BX ₂ to form a perovskite with the chemical formula ABX ₃ . A is a monovalent cation, for example: CH ₃ NH ₃ ⁺ , CH ₃ CH ₂ NH ₃ ⁺ , CH(NH ₂ ) ₂ ⁺ , CH ₃ (CH ₂ ) ₂ NH ₃ ⁺ , CH ₃ (CH ₂ ) ₃ NH ₃ ⁺ , Cs ⁺ , or a combination thereof, B is a divalent cation, such as: Pb ²⁺ , Sn ²⁺ , Ge ²⁺ , or a combination thereof, and X is a halide ion, such as: F ^- , Cl ^- , I ^- , Br ^- , or a combination of the above. The first solvent is used to dissolve the halide. The first solvent can be γ-butyrolactone, dimethylsulfoxide, dimethylformamide, N-methylpyrrolidone, acetonitrile, or a combination of the above. The second solvent is not It is miscible with the first solvent and the halide, for example, it includes chlorobenzene, ethanol, isopropyl alcohol, toluene, ethyl acetate, dimethyl carbonate, diethyl carbonate or a combination of the above.

In one embodiment, the proportion of the halide addition amount relative to the total volume of the first solvent and the second solvent is between 500 and 1200 mg/ml, for example: between 600 and 1000 mg/ml, or between 700 and 900 mg/ml. . In other embodiments, the volume ratio of DMF to DMSO in the first solvent is between 3.5:1 and 4.5:1, or between 3.8:1 and 4.3:1.

Then, the perovskite precursor solution is coated on the substrate, and then the substrate carrying the perovskite solution is subjected to the first stage of low-speed spin coating. This step can make the perovskite solution cover the substrate. To form a perovskite film, the second stage is followed by spin coating at a higher speed, and during the spin coating process, the anti-solvent is dropped onto the substrate carrying the perovskite film. Coating the perovskite solution by spin coating can make the perovskite have good crystallinity and uniform film growth. It can also be sintered by low-temperature heating to reduce grain boundaries and lattice defects, thereby achieving good crystallinity and finally forming Perovskite absorption layer with a thickness of about 250-350nm. In one embodiment, the rotation speed of the first stage of spin coating can be, for example, 1000-3000 rpm, and the time can be 5-15 seconds; the rotation speed of the second stage spin coating can be 4000-7000 rpm, and the time can be, for example, 25-35 seconds. . In the first stage of spin coating, the precursor solution is spread over the entire substrate. During the second stage of spin coating, antisolvent cleaning is added to supersaturate the perovskite. The time at which the antisolvent is dripped is, for example: 5-20 seconds before the end of the second stage of spin coating; or 10-15 seconds. In some embodiments, the antisolvent may include dimethylsulfoxide, dimethylformamide, chlorobenzene, toluene, n-hexane, iodobenzene, secondary butanol, anisole, ethyl acetate, methyl acetate , isopropyl alcohol, or a combination of the above. In some embodiments, the amount of antisolvent added may be, for example, 100-300 μl , or 150-250 μl. Finally, the substrate carrying the perovskite film is annealed to form a perovskite absorption layer. In some embodiments, the annealing temperature may be 100-200°C, 120-180°C, or 140-160°C, and the annealing time may be, for example, 40-70 minutes, or 55-65 minutes. If the annealing temperature is too low, there will be a problem of poor crystallinity; if the annealing temperature is too high, there will be a problem of PbI ₂ secondary phase precipitation. If the annealing time is too short, there will be a problem of poor crystallinity; if the annealing time is too long, there will be a problem of PbI ₂ secondary phase precipitation.

Another embodiment of the present disclosure provides a perovskite solar cell, including: a substrate having a conductive layer; and an electron transport layer disposed on the substrate. In one embodiment, the substrate can be any suitable substrate, such as a glass substrate, a flexible substrate or a polymer substrate, or a transparent or opaque rigid or flexible substrate, but is not limited thereto. In another embodiment, the substrate with the conductive layer may be an FTO substrate, an ITO substrate, a flexible conductive substrate, or a combination of the foregoing. In one embodiment, the material of the electron transport layer includes TiO ₂ , SnO ₂ , PCBM, or a combination of the above.

Furthermore, a perovskite absorption layer is provided on the electron transport layer.

In one embodiment, the intensity ratio of the diffraction peaks in the (220) crystallographic direction and the (310) crystallographic direction of the XRD pattern of the perovskite absorption layer is between 0.9 and 1.1. In another embodiment, the 2θ angle of the XRD pattern of the perovskite absorption layer has strong absorption peaks at 28.2 to 28.8 degrees and 31.2 to 31.8 degrees. The ratio of the peak intensity to the 31.8 degree diffraction peak is between 0.95 and 1.05. In another embodiment, the XRD pattern of the perovskite absorption layer has strong absorption peaks at 2θ angles at 28.5 degrees and 31.8 degrees, and the ratio of the diffraction peak intensities at 28.5 degrees and 31.8 degrees is between Between 0.97 and 1.03.

The hole transport layer is then disposed on the perovskite absorption layer. In one embodiment, the material of the hole transport layer includes Spiro-MeOTAD, PEDOT:PSS, NiOx or a combination of the above.

Finally, the electrode layer is placed on the hole transport layer. In one embodiment, the material of the electrode layer includes Au, Ag, Cu, or a combination of the foregoing.

In order to make the above content and other objects, features, and advantages of the present disclosure more obvious and understandable, preferred embodiments are listed below and described in detail with the accompanying drawings:

[Example] Preparation of perovskite precursor solution:

Example 1

Add CH ₃ NH ₃ Br (MABr) 11.9 mg, PbBr ₂ 39 mg, HC (NH ₂ ) ₂ I (FAI) 98.59 mg, PbI ₂ 277.6 mg, and CsI 9.74 mg to the solvent to form DMF, DMSO, and CB. The volume ratio is 800: 200:20 solvent to prepare 520 μl of perovskite solution.

Example 2

The perovskite precursor solution was prepared according to the steps of Example 1, but the solvent composition was adjusted to a volume ratio of DMF, DMSO and CB of 800:200:40.

Example 3

The perovskite precursor solution was prepared according to the steps of Example 1, but the solvent composition was adjusted to a volume ratio of DMF, DMSO and CB of 800:200:80.

Example 4

The perovskite precursor solution was prepared according to the steps of Example 1, but the solvent composition was adjusted to a volume ratio of DMF, DMSO and CB of 800:200:120.

Comparative example 1

The perovskite precursor solution was prepared according to the steps of Example 1, but no chlorobenzene was added.

Spin-coated perovskite films

The perovskite precursor solutions of Examples 1 to 4 and Comparative Example 1 were spin-coated at a rotation speed of 1950-2050 rpm for 8-12 seconds to coat the perovskite precursor solution on the FTO glass substrate, and then continuously spin-coated at a speed of 5900-6100 rpm. 28-33 seconds. And 10-15 seconds before the end of the spin coating process, drop 135-165 μl chlorobenzene of the anti-solvent on the substrate, and then anneal the perovskite film substrate at 100-200°C for 55-65 minutes to perform the crystal growth process. , and finally form a perovskite light-absorbing layer film.

The precursor solvent compositions of the examples and comparative examples are summarized in Table 1.

Figures 1A to 1C show the grain growth status of the perovskite films of the Examples and Comparative Examples after two-stage spin coating and heat treatment using a scanning electron microscope (SEM). Figure 1A shows that the grain size in Comparative Example 1 is about 50-300nm, and the grain size distribution is relatively uneven; Figure 1B shows that the grain size in Example 1 is about 200-500nm, and compared with the Comparative Example 1. The grain growth is better and there are more large grains; Figure 1C shows that the grain size of Example 3 is about 200-500nm and compared with Example 1, the grain growth is better It is better and shows a tendency of large grain growth. This is because adding chlorobenzene (CB) to the precursor solvent helps to pre-pregnate crystal nuclei and facilitate crystal grain growth. When the chlorobenzene content is low, the effect is not significant; when the chlorobenzene content is increased to a certain proportion, it can significantly promote grain nucleation and growth.

Figure 2 shows the XRD patterns of the perovskite films of Examples 1, 3 and Comparative Example 1 after two-stage spin coating and heat treatment. The XRD patterns can be used to determine the crystallization direction and quality. Figure 2 shows that when the CB content in the solvent increases, the 2θ angle of the XRD pattern has strong absorption at the diffraction peak intensity of 28.2 degrees to 28.8 degrees, that is, there is strong absorption in the (220) crystallographic direction, and, between 31.2 and 31.8 The diffraction peak intensity between degrees has strong absorption, that is, between (310) There is strong absorption in the crystallographic direction. Moreover, the ratio of the diffraction peak intensity of the (220) crystallographic direction to the (310) crystallographic direction is between 0.9 and 1.1. The diffraction peak intensity of the XRD pattern at a 2θ angle of 28.2 degrees to 28.8 degrees is consistent with the diffraction peak intensity of 31.2 degrees and 31.8 degrees. The ratio of emission peak intensities ranges from 0.95 to 1.05. The solvent of Comparative Example 1 does not contain chlorobenzene, and the intensity ratio of the diffraction peaks in the (220)/(310) crystallographic directions in the XRD pattern is less than 0.9. In addition, when the solvent contains chlorobenzene and the content is increased, as in Example 3, the diffraction peak of 13.7 degrees to 14.3 degrees, that is, the (110) crystallization direction, the signal is more symmetrical, indicating that the film quality is better.

Figure 3 is the PL spectrum of the perovskite films of Examples 1 to 3 and Comparative Example 1 after two-stage spin coating and heat treatment. The spectrum of Example 1 shows that there are other defects in the energy gap, and there are sub-bands, which causes the signal to be red-shifted. In Example 2, the addition amount of chlorobenzene is slightly increased, the film properties become better and the defects in the energy gap become fewer. Therefore, the PL signal decreases, indicating that the carrier transmission is good; in Example 3, the addition amount of chlorobenzene is further increased, and it can be confirmed that the defects are significantly reduced. It is speculated that the film grains become larger, the defects existing in the grain boundaries decrease, and the grains The interior is more perfect and there are fewer impurities, so the PL signal is greatly reduced.

Perovskite solar cell production

FTO glass cleaning

Clean the FTO glass (NSG-10) in an ultrasonic device with Triton X100 (1vol%/deionized water), deionized water, acetone and ethanol in sequence for 20 minutes each. Zinc powder and HCl solution are then used to chemically etch the FTO glass to define the positions of the electrodes and perovskite absorption layer.

TiO ₂ /SnO ₂ electron transport layer

A c-TiO ₂ layer was deposited with a solution of titanium diisopropoxide dissolved in ethanol at 450~500°C by spray pyrolysis and annealed at 450°C. Then use SnCl ₂ . The 2H ₂ O solution is spin-coated at a speed of 3500-4000 rpm to form a TiO ₂ /SnO ₂ electron transport layer, and then the film is annealed. After the annealing process, the substrates were immediately transferred to the glove box to prevent the influence of moisture on the crystallinity and film quality.

Spin-coated perovskite absorber layer

Perovskite precursor solutions of different compositions were spin-coated at 1950-2050 rpm for 8-12 seconds to coat the perovskite precursor solution on the FTO glass substrate, and then continuously spin-coated at 5900-6100 rpm for 28-33 seconds. And 10-15 seconds before the end of the spin coating process, drop 135-165 μl chlorobenzene of the anti-solvent on the substrate, and then anneal the perovskite film substrate at 100-200°C for 55-65 minutes to perform the crystal growth process. , and finally form a perovskite light-absorbing layer film.

Spiro-OMeTAD hole transport layer

Dissolve Spiro-OMeTAD in chlorobenzene and add a solution of lithium bis(trifluoromethylsulfonyl)imide (Li-TFSI, Sigma-Aldrich) in acetonitrile and 4-tert-butylpyridine (Sigma-Aldrich) to Prepare the hole transport layer solution. Then spin-coat the Spiro solution at 3500-4000rpm for 20-30 seconds to form the Spiro-OMeTAD hole transport layer.

back electrode layer

80nm gold was evaporated as the back electrode.

Example 5

The perovskite precursor solution of Example 1 was used to prepare a solar cell according to the above-mentioned perovskite solar cell manufacturing method.

Example 6

The perovskite precursor solution of Example 2 was used to prepare a solar cell according to the above-mentioned perovskite solar cell manufacturing method.

Example 7

The perovskite precursor solution of Example 3 was used to prepare a solar cell according to the above-mentioned perovskite solar cell manufacturing method.

Comparative example 2

The perovskite precursor solution of Comparative Example 1 was used to prepare a solar cell according to the above-mentioned perovskite solar cell manufacturing method.

The short-circuit current density Jsc, open-circuit voltage Voc, fill factor FF and photoelectric conversion efficiency PCE of the solar cells of Examples 5 to 7 and Comparative Example 2 were measured and summarized in Table 2.

The results in Table 2 show that as the CB solvent in the precursor solution increases, the short-circuit current density Jsc and open-circuit voltage Voc increase slightly. In addition, the filling factor FF and the photoelectric conversion efficiency PCE have a significant increasing trend, showing that the CB in the precursor solution Solvent-increasing Adding helps to improve the overall quality of the film, thus improving the photoelectric conversion efficiency.

Example 8

Using a perovskite precursor solution with a volume ratio of DMF, DMSO and EA of 800:200:20, a solar cell was produced according to the above perovskite solar cell manufacturing method.

Example 9

Using a perovskite precursor solution with a volume ratio of DMF, DMSO and EA of 800:200:80, a solar cell was produced according to the above perovskite solar cell manufacturing method.

Comparative example 3

Using a perovskite precursor solution with a volume ratio of DMF, DMSO and EA of 800:200:0, a solar cell was produced according to the above perovskite solar cell manufacturing method.

The short-circuit current density Jsc, open circuit voltage Voc, fill factor FF and photoelectric conversion efficiency PCE of the solar cells of Example 5 and Comparative Example 2 were measured. Then, the samples of Example 5 and Comparative Example 2 were placed into an air environment drying box at the same time. (Humidity: 30-40%), after 264hrs, repeat the measurement of Voc, Jsc, F.F. and photoelectric conversion efficiency PCE. The results are shown in Table 3. The results show that the efficiency of the traditional perovskite formula without adding CB solvent increased from 12.75% to 13.59% by about 6.5%, while the efficiency of the perovskite device adding CB solvent increased from 13.47% to 15.73% by about 16.7%. %.

Table 3

The short-circuit current density Jsc, open-circuit voltage Voc, fill factor FF and photoelectric conversion efficiency PCE of the solar cells of Examples 8 to 9 and Comparative Example 3 were measured and summarized in Table 4.

The results in Table 4 show that as the EA solvent in the precursor solution increases, the short-circuit current density Jsc and open circuit voltage Voc increase slightly. In addition, the filling factor FF has a significant increasing trend, showing that the increase in CB solvent in the precursor solution helps Improve the overall quality of the film. In addition, adding EA to the precursor solution also helps to improve the photoelectric conversion efficiency.

Preparation of time-resolved photoluminescence (TRPL) test specimens

Example 10

Spin-coat the perovskite precursor solution of Example 1 (DMF: DMSO: CB=800:200:20) at a rotation speed of 1950-2050 rpm for 5-15 seconds to coat the perovskite precursor solution on the transparent quartz substrate, and The transparent quartz substrate carrying the perovskite absorption layer film and the perovskite absorption layer film are encapsulated to complete the preparation of the TRPL test piece.

Example 11

A TRPL test piece was prepared according to the steps of Example 10, but the composition of the perovskite precursor solution was adjusted to DMF:DMSO:CB=800:200:80.

Comparative example 4

A TRPL test piece was prepared according to the steps of Example 10, but the composition of the perovskite precursor solution was adjusted to DMF:DMSO:CB=800:200:0.

Time-resolved photofluorescence test

The measurement system is set up as follows. The light source is emitted from a 375nm pulse laser and transmitted through the optical fiber into the laser quasi-diameter. The laser is emitted obliquely from the side to the test piece, and the focal length is adjusted to focus on the surface of the test piece. The film on the test piece After absorbing the laser light, it emits fluorescent light with a longer wavelength. After the fluorescent light enters the optical microscope, it is transmitted to the photomultiplier tube through the optical fiber. The photomultiplier tube receives the signal and then transmits it back to the computer. If the light is first introduced into the spectrometer and then into the photoelectric A multiplier tube can measure the fluorescence lifetime of a single wavelength. It is worth noting that this measurement method uses a time-corrected single photon counting system (TCSPC), so the laser source must also be connected to the computer to allow the system to know the starting time when the pulse is emitted. , then the system measures the pulse How long does it take to receive the photoelectron signal after it is sent out? After repeated repetitions and adding up all the messages, you can get a graph of the decay of the light intensity over time. The lifetime of the luminous intensity decay diagram can be calculated by function fitting. The fluorescence lifetime can be used to judge the internal defects of the material. Generally, the longer the lifetime, it means that the carriers are less recombined due to being captured by the trap state, and it is considered that the material has fewer defects.

The free carrier lifetime analysis results are shown in Figure 4. When different CB contents (CB 20, CB 80) are added to the precursor solution, the light intensity decays slower than the comparative example (CB 0), that is, Add CB and as the amount of addition increases, the free carrier lifetime becomes longer.

Although the present disclosure has been disclosed in several preferred embodiments, this is not intended to limit the disclosure. Anyone with ordinary knowledge in the art may make any changes without departing from the spirit and scope of the disclosure. and modifications, therefore the scope of protection of this disclosure shall be subject to the scope of the patent application attached.

Claims (9)

A perovskite precursor solution, including: a plurality of halides, including CH ₃ NH ₃ Br, PbBr ₂ , HC(NH ₂ ) ₂ I, PbI ₂ , CsI, or combinations thereof; a first solvent; a second solvent Solvent; and wherein the first solvent includes dimethyl formamide and dimethyl styrene, the second solvent includes chlorobenzene, and the volume ratio of the first solvent to the second solvent is between 1:0.02 and 1 : between 0.12. For the perovskite precursor solution described in item 1 of the patent application, the volume ratio of the first solvent to the second solvent is between 1:0.04 and 1:0.12. For example, in the perovskite precursor solution described in item 1 of the patent application, the proportion of the plurality of halides relative to the total volume of the first solvent and the second solvent is between 500 and 1200 mg/ml. For example, the perovskite precursor solution described in item 1 of the patent application, wherein the first solvent is dimethylformamide and dimethyl tyrosine, and the dimethylformamide and dimethyl tyrosine The volume ratio is between 3.5:1 and 4.5:1. A method for manufacturing a perovskite absorption layer, including: providing a substrate; adding a perovskite precursor solution to the substrate; performing first-stage spin coating on the perovskite precursor solution to distribute the perovskite precursor solution A perovskite film is formed on the substrate; the substrate carrying the perovskite film is spin-coated in the second stage, and an antisolvent is added to the perovskite film; and the substrate carrying the perovskite film is Annealing to form a perovskite absorption layer, wherein the perovskite precursor solution contains: a plurality of halides, including CH ₃ NH ₃ Br, PbBr ₂ , HC(NH ₂ ) ₂ I, PbI ₂ , CsI, or others Combination; a first solvent; a second solvent; and wherein the first solvent includes dimethyl formamide and dimethyl styrene, the second solvent includes chlorobenzene, and the first solvent and the second solvent The volume ratio is between 1:0.02 and 1:0.12. In the method for manufacturing a perovskite absorption layer described in item 5 of the patent application, in the step of annealing the substrate carrying the perovskite film to form the perovskite absorption layer, the annealing temperature is 100-200°C and The annealing time is 40-70 minutes. In the method for manufacturing a perovskite absorption layer described in item 5 of the patent application, an anti-solvent is added to the perovskite film 10 to 15 seconds before the end of the second spin coating. The method for manufacturing a perovskite absorption layer as described in Item 5 of the patent application, wherein the anti-solvent is chlorobenzene, dimethylstyrene, dimethylformamide, toluene, n-hexane, iodobenzene, secondary Butanol, anisole, ethyl acetate, methyl acetate, isopropyl alcohol, or a combination of the above. In the method for manufacturing a perovskite absorption layer described in item 5 of the patent application, the volume ratio of the first solvent to the second solvent is between 1:0.02 and 1:0.12.

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