High-performance CH3NH3PbI3 perovskite solar cells fabricated under ambient conditions with high relative humidity

Hygroscopic perovskite solar cells are commonly fabricated under conditions of inert atmosphere or low relative humidity (RH). To generate high-performance perovskite light-absorbing layers for super power conversion efficiency (PCE), we fabricated CH3NH3PbI3 solar cells under ambient conditions (RH = 42-48%) by a flowing gas directly from high-RH air. The primary advantage of this technique, together with the casting of a hot solution and quick conduction, enabled us to achieve the highest and average PCEs of 16.32 and 14.27% respectively, with an extremely small deviation of 0.49%. Our research will be of significance for fabricating highly efficient and reproducible perovskite photovoltaics. (c) 2015 The Japan Society of Applied Physics