Enhancement of photoluminescence and water stability of MAPbBr3 perovskite by lead sulfate encapsulation

Abstract

Lead halide perovskite (LHP) has drawn attentions in the optoelectronic field because of its outstanding properties, such as facile bandgap tunability, strong luminescence, and a narrow full width at half-maximum. However, the application of LHP is still limited due to poor stability, especially under exposure to water. In this work, we report a simple strategy of encapsulating $MAPbBr_{3}$ perovskites with lead sulfate by introducing the sulfuric acid solution. The synthesized $MAPbBr_{3}$ perovskites were reacted with sulfate ions and encapsulated with lead sulfate matrix. The bright green-emitting perovskite maintained its luminescence in the liquid water for months because the lead sulfate is water-insoluble. The photoluminescence quantum yield of encapsulated LHPs was remarkably increased from 2.6% up to 80.52 %, and the narrow full width at half-maximum was reduced from 28 nm to 20 nm under the optimized conditions. This study can promote the practical applications of perovskite by solving the water instability issues by matrix encapsulation with lead sulfate.