Inactive impurity stabilizes the highly efficient perovskite photovoltaics

Removing the phase impurities (e.g., hexagonal polytypes, PbI2) in perovskite films is of vital significance to the improvement of long-term operationally stable solar cells. In Science, You et al. report an effective strategy to convert the PbI2 photoactive phase into an inactive phase by doping a small amount of rubidium chloride (RbCl) into perovskite precursor solution. As a result, the perovskite solar cells show the efficiency of power conversion as high as 26.1% (certified 25.6%), enhancing operational stability. Removing the phase impurities (e.g., hexagonal polytypes, PbI2) in perovskite films is of vital significance to the improvement of long-term operationally stable solar cells. In Science, You et al. report an effective strategy to convert the PbI2 photoactive phase into an inactive phase by doping a small amount of rubidium chloride (RbCl) into perovskite precursor solution. As a result, the perovskite solar cells show the efficiency of power conversion as high as 26.1% (certified 25.6%), enhancing operational stability.