Engineering ZnIn2S4 with efficient charge separation and utilization for synergistic accelerate dual-function photocatalysis.

[Display omitted] • A chemically bonded 0D/2D Au/ZIS-V ohmic junction was prepared. • Synergistic effect of built-in electric field, Au-S bonds and Zn vacancies on dual-function photocatalysis. • Au/ZIS-V is suitable for photocatalytic selective alcohol oxidation coupled with H 2 production and CO 2 reduction. • The thermodynamics and kinetics of photoredox were simultaneously improved. • The utilization factor of photoexcited holes to electrons can reach up to 0.99. Combining photocatalytic reduction with organic synthetic oxidation in the same photocatalytic redox system can effectively utilize photoexcited electrons and holes from solar to chemical energy. Here, we stabilized 0D Au clusters on the substrate surface of Zn vacancies modified 2D ZnIn 2 S 4 (ZIS-V) nanosheets by chemically bonding Au-S interaction, forming surfactant functionalized Au/ZIS-V photocatalyst, which can not only synergistic accelerate the selective oxidation of phenylcarbinol to value-added products coupled with clean energy hydrogen production but also further drive photocatalytic CO 2 -to-CO conversion. An internal electric field of Au/ZIS-V ohmic junction and Zn vacancies synchronously promote the photoexcited charge carrier separation and transfer to optimized active sites for redox reactions. Compared with CO 2 reduction in water and the pristine ZnIn 2 S 4 , the reaction thermodynamics and kinetics of CO 2 reduction over the Au/ZIS-V were simultaneously improved about 11.09 and 45.51 times, respectively. Moreover, the photocatalytic redox mechanisms were also profoundly studied by 13CO 2 isotope tracing tests, in situ electron paramagnetic resonance (in situ EPR), in situ X-ray photoelectron spectroscopy (in situ XPS), in situ diffuse reflection infrared Fourier transform spectroscopy (in situ DRIFTS) and density functional theory (DFT) characterizations, etc. These results demonstrate the advantages of vacancies coupled with metal clusters in the synergetic enhancement of photocatalytic redox performance and have great potential applications in a wide range of environments and energy. [ABSTRACT FROM AUTHOR]