Stabilized Wide Bandgap MAPbBr<i>_x</i>I_3–<i>x</i> Perovskite by Enhanced Grain Size and Improved Crystallinity

Abstract

<b>The light instability of CH₃NH₃PbI <i>_x</i> Br_3-<i>x</i> is one of the biggest challenges</b> for its application in tandem solar cells. Here we show that an improved crystallinity and grain size of CH₃NH₃PbI <i>_x</i> Br_3-<i>x</i> films could stabilize these materials under one sun illumination, improving both the efficiency and stability of the wide-bandgap perovskite solar cells.