A Low-Temperature Additive-Involved Leaching Method for Highly Efficient Inorganic Perovskite Solar Cells

Inorganic CsPbI3 perovskite with an optical bandgap ranging from 1.67 to 1.75 eV is a promising light-harvesting material as a top cell in tandem solar cells, but its high fabrication temperature can damage the middle layers or the bottom subcells. Here, an additive-involved leaching method to fabricate CsPbI3 perovskite films is demonstrated, which can decrease the preparation temperature to 100 degrees C. The CsPbI3 perovskite films with high crystallinity are achieved by a solution assisted reaction between DMAPbI(3) and Cs4PbI6 with the leaching of DMA(+), Cs+, and I-. The as-prepared CsPbI3 perovskite films exhibit much superior stability compared to their high-temperature counterparts. As a result, a power conversion efficiency of over 16% is obtained, and the unencapsulated device maintains over 93% of the initial efficiency after aging for 30 days in air with a relative humidity of 10%.

Automated summary

The inorganic CsPbI3 perovskite can be fabricated at a lower temperature using an additive-involved leaching method, resulting in high crystallinity films with superior stability. The prepared films exhibit a power conversion efficiency of over 16% and maintain over 93% of the initial efficiency after aging for 30 days.