Lim J, Rafieh AI, Shibayama N, Xia J, Audinot JN, Wirtz T, Kinge S, Glunz SW, Ding Y, Ding B, Kim H, Saliba M, Fei Z, Dyson PJ, Nazeeruddin MK, and Kanda H
Compositional engineering of organic-inorganic metal halide perovskite allows for improved optoelectrical properties, however, phase segregation occurs during crystal nucleation and limits perovskite solar cell device performance. Herein, we show that by applying tetrabutylammonium bistriflimide as an additive in the perovskite precursor solution, ultra-uniform perovskite crystals are obtained, which effectively increases device performance. As a result, power conversion efficiencies (PCEs) of 24.5% in a cell and 21.2% in a module are achieved, together with high stability under illumination, humidity and elevated thermal conditions., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)