Effective lewis base additive with S-donor for efficient and stable CsPbI2Br based perovskite solar cells

In perovskite solar cells, the Lewis acid-base additives function effectively in high crystalline perovskite film formation and defects passivation. Exploration of effective Lewis acid-base additive to prepare high quality inorganic CsPbI2Br perovskite films with few defects is quite imperative. Here, thioacetamide with S-donor and acetamide with O-donor as Lewis base additives are investigated. It is revealed that a high electron density on S results in better coordination ability with Pb2+ in perovskite solution, leading to form high crystallinity film with lower defect states compared with O-donor. The inorganic CsPbI2Br based perovskite solar cells with thioacetamide additive exhibit the best performance of 15.87% (AM 1.5, 1 sun) and good ambient stability compared with the control device and device with acetamide. This work provides guidance for choosing and designing the effective additives for perovskite solar cells.

Automated summary

The study reveals that the inorganic CsPbI2Br perovskite solar cells with thioacetamide additive exhibit the best performance and good ambient stability, demonstrating the important role of Lewis acid-base additives in improving the performance of the cells.