Electrodeposition Preparation of Perovskite Solar Cells with an Efficiency Exceeding 19

Electrodeposition-prepared perovskite solar cells have the advantages of simple preparation, low costs, large-area preparation, and compatibility with various preparation processes. This has resulted in great potential for the commercial preparation of perovskite solar cells. However, the efficiency of electrodeposition-prepared perovskite solar cells is very low, preventing further research. The low efficiency of these perovskite solar cells may be related to the lack of research on solvent regulation, composition regulation, and passivation regulation or because of the incomplete reaction between electrodeposited lead compounds and halides. Herein, hydroiodic acid is first used to convert lead dioxide (PbO₂) into lead iodide (PbI₂), and then react it with different compositions of halides in air to obtain perovskite films. This approach minimizes the formation of by-products that typically arise from direct reactions between PbO₂ and halides, thereby enhancing film purity and crystallinity. Through the synergistic effect of N,N-dimethylformamide solvent engineering, and methylammonium chloride composition engineering, the surface smoothness, grain size, light absorption, and carrier transport properties of the perovskite films prepared by electrodeposition can be significantly improved. The efficiency of the electrodeposition-prepared perovskite solar cells increased from 8.41% to 17.28%. Moreover, the efficiency is further improved to 19.30% via passivation engineering using formamidinium iodide.