Abstract:

The energy conversion efficiency of CH₃NH₃PbI₃ (MAPPbI₃) perovskite solar cells is closely related to the quality of the perovskite film. To obtain high quality perovskite films, the film preparation method and process were optimized. It was found that the green solvents, propylene glycol methyl ether acetate and glycerol, can promote nucleation of PbI₂ particles, provide heterogeneous nucleation sites for CH₃NH₃PbI₃ perovskite crystals, and thus facilitate the rapid growth of perovskite crystals. Compared to perovskite films treated with the common toxic solvent chlorobenzene, films treated with propylene glycol methyl ether acetate and glycerol have larger grain size, lower root-mean-square value, and greater surface roughness optimization. This can result in a uniform, full-coverage perovskite film that is close to the perovskite carrier diffusion length. The performance of devices under different treatment conditions was tested and it was found that compared to CH₃NH₃PbI₃ perovskite solar cells treated with chlorobenzene (energy conversion efficiency of 17.86%), the device treated with green solvent glycerol had the highest efficiency of 21.60%, which is an increase of nearly 21%. These experimental results have some reference value and guiding significance for researchers in this field to obtain environmentally friendly high-quality perovskite type solar cells in the future.

Key words: perovskite solar cell, green antisolvent, morphology optimization, device efficiency