InVO4/β-AgVO3 Nanocomposite as a Direct Z-Scheme Photocatalyst toward Efficient and Selective Visible-Light-Driven CO2 Reduction

Photocatalytic CO 2 reduction to solar fuel is a promising route to alleviate the ever-growing energy crisis and global warming. Herein, to enhance photoconversion efficiency of CO 2 reduction, a series of direct Z-scheme composites consisting of β-AgVO 3 nanoribbons and InVO 4 nanoparticles (InVO 4 /β-AgVO 3 ) are prepared via a facile hydrothermal method and subsequent in situ growth process. The prepared InVO 4 /β-AgVO 3 composites exhibit enhanced photocatalytic activity for reduction of CO 2 to CO under visible-light illumination. A CO evolution rate of 12.61 μmol·g –1 ·h –1 is achieved over the optimized 20% In–Ag without any cocatalyst or sacrificial agent, which is 11 times larger than that yielded by pure InVO 4 (1.12 μmol·g –1 ·h –1 ). Moreover, the CO selectivity is more than 93% over H 2 production from the side reaction of H 2 O reduction. Significantly, based on the results of electron spin resonance (ESR) and in situ irradiated XPS tests, it is proposed that the synthesized InVO 4 /β-AgVO 3 catalysts comply with the direct Z-scheme transfer mechanism. Significantly improved photocatalytic activities for selective CO 2 reduction could be primarily ascribed to effective separation of photoinduced electron–hole pairs and enhanced reducibility of photoelectrons at the conduction band of InVO 4 . This work provides a new insight for constructing highly efficient photocatalytic CO 2 reduction systems toward solar fuel generation.