CN-122003080-A - Perovskite precursor solution based on non-halogen lead source, perovskite light absorption layer and preparation method of perovskite solar cell

CN122003080ACN 122003080 ACN122003080 ACN 122003080ACN-122003080-A

Abstract

The invention belongs to the technical field of perovskite solar cell preparation, and discloses a perovskite precursor solution based on a non-halogen lead source, a perovskite light absorption layer and a perovskite solar cell preparation method. The preparation method of the perovskite precursor solution based on the non-halogen lead source comprises the steps of dissolving the non-halogen lead source, the organic halide AX and the organic acid in a mixed solvent, and continuously stirring at 50-70 ℃ until the solid is completely dissolved, so as to obtain the perovskite precursor solution. The method can stably prepare the high-quality film under the high-humidity air condition without depending on inert atmosphere, greatly reduces the process complexity and the production cost, improves the photoelectric conversion efficiency of the device, enhances the environmental tolerance of the device, and ensures that the device still maintains good long-term stability under the action of air humidity.

Inventors

WANG ZHEN
BAO YING
LI XIU
ZHANG BAOSEN
ZHANG XIANGDAN
DONG MIAO

Assignees

河南工程学院

Dates

Publication Date: 20260508
Application Date: 20251225
Priority Date: 20251224

Claims (10)

1. The preparation method of the perovskite precursor solution based on the non-halogen lead source is characterized in that the non-halogen lead source, the organic halide AX and the organic acid are dissolved in a mixed solvent, and stirring is continuously carried out at 50-70 ℃ until the solid is completely dissolved, so as to obtain the perovskite precursor solution; Wherein A in AX represents organic cation, X represents halogen anion, the raw material ratio is non-halogen lead source, AX, organic acid, mixed solvent=1 mmol to (3-3.5) mmol to (0.2-3) mmol to (0.7-1) mL, and the mixed solvent is composed of DMF and DMSO according to DMF, DMSO= (4-9) to 1 by volume ratio.
2. The method of preparing a non-halogenated lead source based perovskite precursor solution according to claim 1, wherein the non-halogenated lead source is Pb (SCN) 2 .
3. The method of preparing a lead non-halide source based perovskite precursor solution according to claim 1, wherein AX is CH 3 NH 3 I or CH (NH 2 ) 2 I).
4. The method for preparing a lead-halogen-free source-based perovskite precursor solution according to claim 1, wherein the organic acid is formic acid, acetic acid or oxalic acid.
5. A method for preparing a perovskite light absorbing layer by using the perovskite precursor solution based on the non-halogen lead source according to any one of claims 1-4, which is characterized in that the perovskite precursor solution is dripped on the surface of a substrate in an atmosphere of 10-90% RH, spin-coating is carried out to form a film, and an antisolvent is dripped about 5-10 s before the spin-coating process is nearly finished to form an intermediate phase film, and the intermediate phase film is annealed to obtain the perovskite light absorbing layer.
6. The method for preparing a perovskite light absorbing layer based on a non-halogen lead source perovskite precursor solution as claimed in claim 5, wherein the antisolvent is ethyl acetate, methyl butyrate or methyl formate.
7. The method for preparing the perovskite light-absorbing layer based on the perovskite precursor solution of the non-halogen lead source according to claim 5, wherein the spin coating speed is 4000-5000 rpm and the time is 20-30 s, the annealing adopts a two-step annealing mode, namely, pre-annealing for 1-5 min at 60-80 ℃ and further annealing for 10-15 min at 90-120 ℃, and the volume ratio of the perovskite precursor solution to the antisolvent is 1:8-10.
8. A method for preparing a perovskite solar cell by using the perovskite precursor solution based on the non-halogen lead source according to any one of claims 1-4, which is characterized in that the perovskite solar cell sequentially comprises a transparent conductive substrate, an electron transport layer, a perovskite light absorption layer, a hole transport layer and a metal electrode from bottom to top, wherein the preparation steps of the perovskite solar cell are as follows: S1, cleaning and preprocessing a transparent conductive substrate; S2, spin-coating an electron transport layer precursor solution on the transparent conductive substrate obtained in the step S1, and annealing to obtain an electron transport layer; S3, dropwise adding a perovskite precursor solution on the surface of the electron transport layer obtained in the step S2 in an atmosphere of 10-90% RH, spin-coating to form a film, and dropwise adding an antisolvent to form an intermediate phase film before the spin-coating process is nearly finished; S4, spin-coating a hole transport layer precursor solution on the perovskite light absorption layer obtained in the step S3 to obtain a hole transport layer; And S5, evaporating a metal electrode on the hole transport layer obtained in the step S4 to obtain the perovskite solar cell.
9. The method for preparing a perovskite solar cell based on a non-halogen lead source perovskite precursor solution as claimed in claim 8, wherein the antisolvent is ethyl acetate, methyl butyrate or methyl formate.
10. The method for preparing the perovskite solar cell based on the non-halogen lead source perovskite precursor solution is characterized in that spin coating speed is 4000-5000 rpm, time is 20-30 s, annealing adopts a two-step annealing mode, namely pre-annealing for 1-5 min at 60-80 ℃ and further annealing for 10-15 min at 90-120 ℃, the volume ratio of the perovskite precursor solution to the antisolvent=1: (8-10), the transparent conductive glass is FTO conductive glass or ITO conductive glass, the electron transport layer is SnO 2 or TiO 2 , the hole transport layer is Spiro-OMeTAD, and the metal electrode is Au or Ag.

Description

Perovskite precursor solution based on non-halogen lead source, perovskite light absorption layer and preparation method of perovskite solar cell Technical Field The invention belongs to the technical field of perovskite film preparation, and particularly relates to a perovskite precursor solution based on a non-halogen lead source, a perovskite light absorption layer and a perovskite solar cell preparation method. Background Organic-inorganic lead halide perovskite materials are considered as photoelectric semiconductor materials with great development potential due to the advantages of adjustable band gap, high carrier mobility, long carrier diffusion length, low exciton binding energy and the like. Since early perovskite solar cell efficiency was reported for the first time, the energy conversion efficiency of the perovskite solar cell is greatly improved in a short time, the cell device efficiency is close to the level of a crystalline silicon solar cell, and the perovskite solar cell is regarded as a potential scheme of a new generation of alternative silicon-based technology. Although perovskite solar cells have made a significant breakthrough in efficiency, the intrinsic instability of perovskite materials to ambient humidity is still an important factor limiting their commercialization. In the prior art, a high-quality perovskite thin film is usually required to be prepared in a glove box with an inert atmosphere, which greatly increases the equipment cost and the process repeatability and is not beneficial to large-scale manufacturing. The continuity, compactness, grain size and defect density of the perovskite film have decisive influence on the efficiency and stability of the device, so how to prepare a high-quality perovskite film in an air environment becomes an important research direction in the field. To achieve stable film formation in an air environment, some studies have attempted to improve film morphology and moisture resistance by optimizing precursor formulations, adjusting process conditions, or introducing additives, among other means. Among them, thiocyanate ion (SCN -) as a pseudo halogen ion has a strong binding capacity with lead ion, and Pb (SCN) 2 as a lead source can improve the moisture resistance stability of the film, which has been proved to be effective in retarding the degradation of perovskite films in high humidity environments. In addition, the perovskite thin film and the corresponding photovoltaic device obtained by adopting the one-step method or the two-step method process show higher humidity tolerance and long-term stability. However, the existing Pb (SCN) 2 -based air preparation method still has obvious defects in film forming quality. Due to the strong coordination between the thiocyanate ions and the lead ions, the nucleation and crystallization kinetics of the precursor solution can be obviously influenced, so that the problems of non-uniform nucleation, slow crystallization and the like are more likely to occur in the film forming process, and the defects of insufficient surface coverage rate, uneven grain size, more holes and higher roughness of the film are caused. These defects not only can increase carrier recombination and reduce the photoelectric conversion efficiency of the device, but also can cause poor interface contact between the hole transport layer and the perovskite light absorption layer, thereby further aggravating energy loss and stability degradation of the device. In addition, water molecules commonly existing in the air environment can compete with the SCN-containing precursor or promote heterogeneous conversion of the intermediate phase, so that the crystallization process of the Pb (SCN) 2 system is more complex and uncontrollable, and the formation probability of film defects is increased. Therefore, despite the excellent moisture resistance potential of Pb (SCN) 2, the film formation process under air conditions still lacks effective means of regulation, and it is difficult to directly obtain continuous, dense and high crystalline quality perovskite films. Disclosure of Invention Aiming at the defect that a high-quality perovskite film generally needs to be prepared in a glove box with an inert atmosphere but cannot be prepared in an air environment in the prior art, one of the purposes of the invention is to provide a preparation method of a perovskite precursor solution based on a non-halogen lead source, the other purpose is to provide a preparation method of a perovskite light absorption layer based on the non-halogen lead source, and the third purpose is to provide a preparation method of a perovskite solar cell based on the non-halogen lead source. In order to achieve one of the above purposes, the technical scheme adopted by the invention is as follows: The preparation method of perovskite precursor solution based on non-halogen lead source comprises the steps of dissolving non-halogen lead source, organic halide AX and org