Coupling Organic Synthesis and Hydrogen Evolution over Composite WO3/ZnIn2S4 Z-Scheme Photocatalyst

Coupling photocatalytic hydrogen (H-2) evolution with selective organic synthesis in one redox cycle showcases great potential for the coinstantaneous utilization of photoexcited electrons and holes toward sustainable production of value-added fuels and chemicals. Herein, we construct one-dimensional/two-dimensional (1D/2D) WO3/ZnIn2S4 (WO3/ZIS) hierarchical Z-scheme composites for bifunctional integrated light-driven H-2 production and biomass-derived aromatic alcohol conversion. The superior photoactivity and selectivity over WO3/ZIS composites compared with that over bare WO3 nanorods (NRs) and ZIS nanosheets (NSs) can be attributed to the assembly of the Z-scheme heterostructure. The construction of WO3/ZIS direct Z-scheme composites not only facilitates the charge separation dynamics by transporting photoinduced electrons and holes to spatially separated redox sites but also steers the selectivity of targeted products by tuning the energy band potentials to endow electrons and holes with stronger reduction and oxidation abilities. The mechanistic studies combining the control experiments and electron paramagnetic resonance spectroscopy validate the free radical mechanism of the benzyl alcohol photooxidation reaction. It is anticipated that this work would offer a conducive paradigm for the ingenious design of high-performance Z-scheme heterostructured catalysts toward the solar light-driven collaborative redox of H-2 production and selective organic synthesis.

Automated summary

This study demonstrates the great potential of coupling photocatalytic hydrogen evolution with selective organic synthesis for sustainable production of value-added fuels and chemicals. The researchers construct one-dimensional/two-dimensional WO3/ZnIn2S4 hierarchical composites that exhibit superior photoactivity and selectivity compared to bare WO3 nanorods and ZIS nanosheets. The assembly of the Z-scheme heterostructure facilitates charge separation dynamics and tunes the energy band potentials to enhance the reduction and oxidation abilities of electrons and holes. The mechanism studies confirm the free radical mechanism of the photooxidation reaction and offer insights for the design of high-performance Z-scheme heterostructured catalysts.