CN-121985709-A - Surface treatment method of single crystal perovskite film, perovskite battery and preparation method thereof

CN121985709ACN 121985709 ACN121985709 ACN 121985709ACN-121985709-A

Abstract

The invention discloses a surface treatment method of a single crystal perovskite film, a perovskite battery and a preparation method thereof, wherein the preparation method of the perovskite battery comprises the following steps of S1, sequentially preparing a bottom electrode and a hole transmission layer on a substrate, S2, growing an initial single crystal perovskite film on the hole transmission layer, S3, applying a chemical polishing agent solution on the surface of the single crystal perovskite film for chemical polishing, wherein the chemical polishing agent solution does not contain abrasive particles, stopping polishing after the surface roughness RMS of the single crystal perovskite film is smaller than 5nm after chemical polishing, S4, applying a passivating agent solution on the surface of the single crystal perovskite film after chemical polishing for post passivation, and S5, sequentially preparing an electron transmission layer and a back electrode on the single crystal perovskite film after post passivation to obtain the perovskite battery. The invention optimizes the surface of the monocrystalline perovskite film and improves the photoelectric conversion efficiency and stability of the perovskite solar cell.

Inventors

ZOU GUIFU
SUN XIANGLE
ZHANG RONG
LU ZHENG
TIAN DEYU

Assignees

苏州大学
苏州益恒能源科技有限公司

Dates

Publication Date: 20260505
Application Date: 20260408

Claims (10)

1. A method of preparing a perovskite battery, comprising the steps of: S1, sequentially preparing a bottom electrode and a hole transport layer on a substrate; S2, growing an initial single crystal perovskite film on the hole transport layer; S3, applying a chemical polishing agent solution to the surface of the single crystal perovskite film for chemical polishing, wherein the chemical polishing agent solution does not contain abrasive particles, and stopping polishing after the chemical polishing is performed until the surface roughness RMS of the single crystal perovskite film is less than 5 nm; s4, applying a passivating agent solution on the surface of the single crystal perovskite film after chemical polishing for post passivation; and S5, sequentially preparing an electron transport layer and a back electrode on the single crystal perovskite film after post passivation to obtain the perovskite battery.
2. The method for manufacturing a perovskite battery according to claim 1, wherein in step S3, polishing is stopped after chemical polishing until the surface roughness RMS of the single crystal perovskite thin film is less than 3nm, and in step S4, a passivation layer is formed on the single crystal perovskite thin film by post passivation treatment, wherein the surface roughness RMS of the passivation layer is less than 2.5nm.
3. The preparation method of the perovskite battery according to claim 1, wherein in the step S3, the chemical polishing agent solution is a mixed solution composed of chlorobenzene and gamma-butyrolactone, the mass of the chlorobenzene is 80% -90% of the total mass of the chemical polishing agent solution, and in the step S4, the passivating agent solution is a chlorobenzene solution of tetrabutylammonium iodide, and the concentration of the tetrabutylammonium iodide is 0.5mg/ml-5mg/ml.
4. The method for preparing a perovskite battery according to claim 3, wherein the mass ratio of chlorobenzene to gamma-butyrolactone in the chemical polishing solution is 85:15, and the concentration of tetrabutylammonium iodide in the passivating solution is 1mg/ml.
5. The method for preparing a perovskite battery according to claim 1, wherein in the step S3, the chemical polishing is performed by spin-coating a chemical polishing agent solution, the spin-coating rotation speed is 2000rpm-4000rpm, the spin-coating time is 15-45S, and in the step S4, the post-passivation is performed by spin-coating a passivating agent solution, the spin-coating rotation speed is 2000rpm-4000rpm, and the spin-coating time is 15-45S.
6. The method for preparing a perovskite battery according to claim 1, wherein in the step S2, the single crystal perovskite thin film is grown by a space confinement method, the prepared perovskite precursor solution is dripped on a conductive substrate of the hole transport layer, another conductive substrate is covered to form a sandwich structure, the sandwich structure is subjected to heat treatment, crystals are crystallized and grown in the middle of the sandwich structure, and the single crystal perovskite thin film is obtained, wherein the thickness of the single crystal perovskite thin film is 30-40 micrometers.
7. The method for preparing the perovskite battery according to claim 6, wherein the perovskite precursor solution comprises lead methyl ammonium iodide and solvent gamma-butyrolactone, the concentration of the lead methyl ammonium iodide in the perovskite precursor solution is 1.2mol/L-1.8mol/L, and other additives are not added into the perovskite precursor solution.
8. The method for preparing the perovskite battery according to claim 1, wherein the substrate is ITO conductive glass, the bottom electrode is an Ag bottom electrode, the electron transport layer is fullerene carbon 60, the back electrode is an Ag back electrode, the hole transport layer adopts poly [ bis (4-phenyl) (2, 4, 6-trimethylphenyl) amine ] with a number average molecular weight of 20000-50000, the thickness of the bottom electrode is 80nm-120nm, and the thickness of the back electrode is 80-120nm.
9. A perovskite battery, characterized in that it is prepared by a method according to any one of claims 1-8.
10. A surface treatment method of a single crystal perovskite film is characterized by comprising the steps of applying a chemical polishing agent solution to the surface of the single crystal perovskite film for chemical polishing, wherein the chemical polishing agent solution does not contain abrasive particles, the chemical polishing agent solution is a mixed solution composed of chlorobenzene and gamma-butyrolactone, and applying a passivating agent solution to the surface of the single crystal perovskite film after chemical polishing for post-passivation, and the passivating agent solution is a chlorobenzene solution of tetrabutylammonium iodide.

Description

Surface treatment method of single crystal perovskite film, perovskite battery and preparation method thereof Technical Field The invention belongs to the technical field of solar cell preparation, and particularly relates to a surface treatment method of a monocrystalline perovskite film, a perovskite cell and a preparation method thereof. Background Metal perovskite halides have been attracting attention in recent years as next-generation optoelectronic materials due to their unique excellent photophysical properties, including high carrier mobility, high defect tolerance, excellent light absorption capability, and high crystal symmetry. However, the polycrystalline perovskite thin film weakens device performance due to the presence of a large number of grain boundaries and high density charge defects, and promotes erosion of moisture and ion migration. In contrast, single crystal perovskite thin films have significant advantages over polycrystalline perovskite thin films in that, without grain boundaries, single crystal perovskite thin films exhibit significantly reduced trap density, significantly enhanced carrier mobility, and superior environmental stability, these inherent characteristics making single crystal perovskite thin films ideal candidates for fabricating durable high performance solar cells. Although solution-based methods of growing single crystal perovskite thin films have significant advantages in manufacturing large area single crystal perovskite thin films for photovoltaic applications, rapid evaporation of residual solution during growth may lead to the formation of polycrystalline structures and deposition of impurities, thereby reducing the quality of the single crystal perovskite thin film surface. Notably, the surface defect density of single crystal perovskite films is about four orders of magnitude higher than its bulk phase, even exceeding that of polycrystalline perovskite films. Together, these findings suggest that surface optimization of single crystal perovskite thin films is a key factor in high performance device development. Disclosure of Invention In view of all or part of the shortcomings of the prior art, the invention aims to provide a surface treatment method of a single crystal perovskite thin film, a perovskite battery and a preparation method thereof, optimize the surface of the single crystal perovskite thin film and improve the photoelectric conversion efficiency and stability of the perovskite solar cell. In order to achieve the above object, the present invention provides the following technical solutions: The invention provides a preparation method of a perovskite battery, which comprises the following steps: S1, sequentially preparing a bottom electrode and a hole transport layer on a substrate; S2, growing an initial single crystal perovskite film on the hole transport layer; S3, applying a chemical polishing agent solution to the surface of the single crystal perovskite film for chemical polishing, wherein the chemical polishing agent solution does not contain abrasive particles, and stopping polishing after the chemical polishing is performed until the surface roughness RMS of the single crystal perovskite film is less than 5 nm; s4, applying a passivating agent solution on the surface of the single crystal perovskite film after chemical polishing for post passivation; and S5, sequentially preparing an electron transport layer and a back electrode on the single crystal perovskite film after post passivation to obtain the perovskite battery. The initial single crystal perovskite film surface has protrusions, which are typically impurities (either polycrystalline or small single crystals grown from the precursor). If the surface with the raised part, namely the high defect density, is directly removed through mechanical polishing engineering, the defect density of the surface of the single crystal perovskite film can be effectively reduced, but secondary defects such as scratches and lattice dislocation can be introduced. If the molecular surface passivation is only used for interacting with uncoordinated metal ions such as Pb 2+ in the single crystal perovskite film and filling halogen vacancies, the defect density of the surface of the single crystal perovskite film can be effectively reduced, but the surface morphology nonuniformity caused by the protruding part cannot be eliminated, so that the uniformity of carrier transmission is damaged. The method of mechanical polishing or molecular passivation alone is used to solve the surface problem of the single crystal perovskite film, which has the defect. According to the invention, the surface planarization of the single crystal perovskite film is realized through the selective reaction of chemical polishing, then the defect density of the surface of the single crystal perovskite film is reduced through a post passivation method, and the surface defect passivation is performed while the surface of the si