Preparation method for perovskite thin film capable of improving purity and reducing pin holes

Abstract

The invention provides a preparation method for a perovskite thin film capable of improving purity and reducing pin holes. The preparation method specifically comprises the steps of dissolving CH<3>NH<3>X (x can be Cl, Br or I) powder into anhydrous isopropyl alcohol to form a CH<3>NH<3>X solution, and then spraying the solution on a substrate by a spray pyrolysis method to form a CH<3>NH<3>X film layer; then covering the CH<3>NH<3>X thin film with the substrate coated with a PbX<2> thin film; and carrying out high-temperature annealing to enable the CH<3>NH<3>X steam molecules to be dispersed in the PbX<2> thin film, wherein the PbX<2> existing in mesopores also can be fully reacted. According to the preparation method, the CH<3>NH<3>X is in contact reaction with the PbX<2> thin film in a form of thin film; and compared with the powder type contact, the point contact can be replaced by surface contact, so that the problem of the pin holes caused by uneven contact existing in the current powder contact method can be effectively solved.

Description

technical field [0001] The invention relates to the technical field of solar cells, in particular to a method for preparing a perovskite thin film with improved purity and reduced pinholes. Background technique [0002] Solar cells can directly convert solar energy into electrical energy. Since solar energy is an inexhaustible clean energy source, solar cells are an important countermeasure for human beings to cope with the energy crisis and seek sustainable development. Currently, crystalline silicon solar cells account for 89% of the photovoltaic market share. However, expensive raw materials and cumbersome cell processes limit the long-term development of crystalline silicon solar cells. In the past decade, thin-film solar cells include silicon-based thin-film, Cu(In,Ga)Se 2-x S x And CdTe batteries have also begun to achieve large-scale industrialization. As an outstanding representative of the third generation of solar cells, perovskite solar cells are a new type of...

AI Technical Summary

Problems solved by technology

But with the powder contact method, due to the CH 3 NH 3 I powder particles are larger, making CH 3 NH 3 I particles and PbI 2 The thin film contact cannot form a good contact, and it is easy to form pinholes in the prepared perovskite film, which greatly reduces the quality of the film and increases leakage, which in turn affects the photovoltaic performance.

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