MAPbBr 3 /Bi 2 WO 6 Z-scheme-heterojunction photocatalysts for photocatalytic CO 2 reduction

Photocatalytic CO 2 reduction has emerged as a promising strategy for converting solar energy into valuable chemicals, capturing the attention of scientists across various disciplines. Organic and inorganic perovskites, particularly methylammonium lead bromide (MAPbBr 3 ), have demonstrated potential in this field due to their remarkable visible-light response and carrier transport properties. However, the catalytic performance of pristine MAPbBr 3 has been limited by severe charge recombination, hindering its applicability in photocatalytic systems. Here, we show that a MAPbBr 3 /Bi 2 WO 6 (MA/BWO) heterojunction significantly enhances photocatalytic CO 2 reduction performance compared to individual pristine MA or BWO. This enhancement is evidenced by the superior performance of the 25% MA/BWO composite, which exhibits CO and CH 4 release rates of 1.82 μmol/g/h and 0.08 μmol/g/h, respectively. This improvement is attributed to the direct Z-scheme heterojunction formed between MAPbBr 3 and Bi 2 WO 6 , which facilitates efficient charge separation and suppresses charge recombination. The results challenge the previous understanding of MAPbBr 3 -based photocatalysts and demonstrate a novel approach for developing highly active organic and inorganic perovskite photocatalysts. The successful application of the MA/BWO heterojunction in photocatalytic CO 2 reduction expands the scope of organic and inorganic perovskites in the field of renewable energy conversion. By providing a broader perspective, our findings contribute to the ongoing efforts towards sustainable energy solutions, appealing to scientists from various disciplines aiming to address global environmental challenges. Graphical abstract