Efficient and Stable Carbon-Based All-Inorganic CsPbIBr2 Perovskite Solar Cells Obtained via Treatment by Biological Active Substance Additive

Stability has always been a major challenge in the commercialization of perovskite solar cells (PSCs). All-inorganic perovskite semiconductor materials have attracted much attention in the field and are considered to be the best choice to solve this challenge due to their good thermal stability. However, all-inorganic perovskite films contain a high density of defects that provide channels for nonradiative recombination of charges and ion transport, which seriously threaten the stability of PSCs. Different defects have corresponding passivation mechanisms. Through the introduction of multifunctional additives, multiple passivation effects can be realized at the same time, and the power conversion efficiency (PCE) can be greatly improved. Herein, the introduction of the small biological molecule (adenosine) as the additive into the perovskite precursor can maximize the passivation mechanisms of Lewis bases. The doping of adenosine improves the crystallinity, reduces the density of trap states and enhances the light absorption, and finally obtains PSCs with the best PCE of 10.24%, which is 30.8% higher than that of the standard device. In addition, adenine is also introduced as a comparative study, and the treated CsPbIBr2 PSC with a PCE of 9.72% is finally obtained.