Nanostructured ZnO/ZnS with Type-II Hetero-junction for Efficient CO₂ Photoreduction

Photocatalytic CO₂ reduction driven by solar light is a green approach that can decrease the greenhouse effect induced by high CO₂ concentration in the atmosphere and generate carbon-based chemicals/fuels as well. In this paper, non-metal co-catalysts ZnO/ZnS type-II hetero-junction nanoparticles with a rough surface were prepared through a hydrothermal process. When used as a photocatalyst for CO₂ reduction, the optimal one showed good cycle stability and a higher yield rate of 27.8 µmol·g⁻¹·h⁻¹ for CO₂ conversion into CO. The outstanding catalytic activity originated from i) the rich interfaces between ZnO and ZnS in the nanoscale could significantly reduce the delivery path of carriers and improve the utilization efficiency of photo-excited electron/hole pairs and ii) enriched surface oxygen defects could supply much more reaction active sites for CO₂ adsorption.