Self-assembly of MAPbBr₃/Pb-MOF heterostructures with enhanced photocatalytic CO₂ reduction performance and stability

The appropriate and adjustable band structure and positive visible-light response enable the halide perovskite MAPbBr(3) to be a promising photocatalyst for CO2 reduction. Considering the extremely poor water resistance and severe carrier complexation trends, rational design and control of steam stable MAPbBr(3)-based heterojunction nanocrystals to exploit their potential for photocatalytic CO2 reduction in steam is important while being a challenging topic. Here, an efficient MAPbBr(3)/Pb-MOF heterojunction photocatalyst is developed, ensuring in situ growth of Pb-MOF on the surface of the perovskite via a self-sacrificial template method, thus creating tightly connected interfaces to mitigate the sluggish charge transfer due to the discontinuous interfaces. The experimental results confirm that construction of MAPbBr(3)/Pb-MOF heterojunctions suppresses the recombination of photogenerated carriers. Meanwhile, the prepared MAPbBr(3)/Pb-MOF exhibits better steam stability, CO2 adsorption capacity, and higher separation efficiency of photogenerated carriers. The heterostructure enables the photocatalytic reduction of CO2 to CO at an excellent rate of 21.5 mu mol g(-1) under visible light irradiation, which is 4.8 times larger than that of pristine MAPbBr(3).