Researchers from East China University of Science and Technology and Australia-based Griffith University have examined the effects of surface decoration of perovskites on the stability of resulting perovskite solar cells. They reported that such configurations have shown to be more stable than the untreated surface of perovskites.

The team reported a chelation strategy for surface engineering of CsPbI2Br perovskite, in which dithiocarbamate molecules can be coordinate to surface Pb sites via strong bidentate chelating bonding. Such chelated CsPbI2Br perovskite can realize excellent passivation of surface under-coordinated defects, reaching a power conversion efficiency of 17.03% and an open-circuit voltage of 1.37 V of CsPbI2Br solar cells.

More importantly, this chelation strategy enabled excellent device stability by maintaining 98% of their initial efficiency for over 1400 h in ambient condition. The team's findings provide scientific insights on the surface engineering of perovskite that can facilitate the further development and application of perovskite optoelectronics.