Embedding CsPbBr3 Quantum Dots into an In2O3 Nanotube for Selective Photocatalytic CO2 Reduction to Hydrocarbon Fuels

Halide perovskite quantum dots (QDs) are one of the most prospective candidates for photocatalytic CO 2 reduction, but their photocatalytic performances are far from satisfactory due to structural instability and severe charge recombination. In this study, we demonstrated a CsPbBr 3 QDs/In 2 O 3 hierarchical nanotube (CPB/IO) for efficient CO 2 conversion, in which CsPbBr 3 QDs were well-dispersed on the In-MOF-derived In 2 O 3 nanotube by a facile self-assembly process. The optimized CPB/IO catalyst displayed an enhanced photocatalytic CO 2 performance with a (CO + CH 4 ) generation rate of 16.37 μmol·g –1 ·h –1 upon simulated solar illumination without a photosensitizer and sacrificial agent, which is 3.59 times stronger than that of pristine CsPbBr 3 QDs (4.56 μmol·g –1 ·h –1 ). Besides, the modified CsPbBr 3 QD catalyst exhibited an obvious increase of CH 4 selectivity and excellent stability after four cycles. The unique zero-dimensional (0D)/one-dimensional (1D) heterostructure and matching band potentials between CsPbBr 3 and In 2 O 3 supply an intimate interfacial contact, numerous active sites, and effective charge transfer for CO 2 photoreduction. This work can inspire the formation of novel halide-perovskite-involving photocatalysts for solar fuel formation.