Stable MAPbBr3@PbBr(OH) composites with high photoluminescence quantum yield: Synthesis, optical properties, formation mechanism, and catalytic application

The disappointing stability of perovskites against polar solvent and light irradiation severely hinders their application in photocatalysis. Here, we design a facile and reliable approach to synthesize MAPbBr3@PbBr(OH) composites with outstanding photoluminescence quantum yield (PLQY) of 74.4–90.6% and high stability under various harsh environments by simply introducing ZIF-67 or ZIF-8 in perovskite precursor solution. Benefiting from the preferential interaction between ZIF-67/ZIF-8 and MABr in the precursor step, the transformation of PbBr2 to PbBr(OH) triggered by ZIF-67/ZIF-8 occurs simultaneously with the formation of MAPbBr3 during the subsequent injection of toluene. PL intensity of the MAPbBr3@PbBr(OH) obtained by self-assembly of MAPbBr3 into PbBr(OH) can maintain above 95% of the initial after soaking in a wide variety of polar solvents for 210 days. Meanwhile, the composite also shows enhanced stability against continuous ultraviolet illumination. Moreover, the MAPbBr3@PbBr(OH) can be used in aqueous solution as photocatalyst for degradation of organic dye methylene green (MG) at room temperature. The MG degradation efficiency is observed to above 90% within 3 h. This work not only provides a reliable and controllable method for the synthesis of stable perovskites with high PLQY, but also pave the way for the use of perovskites as efficient photocatalyst in catalytic applications.