RuS2@CN-x with exposed (200) facet as a high-performance photocatalyst for selective C–C bond cleavage of biomass coupling with H–O bond cleavage of water to co-produce chemicals and H2

Abstract

The selective photocatalytic C–C bond cleavage of biomass coupling with H–O bond cleavage of water for co-producing chemicals and H₂ is of great significance, but limited successes have been reported. In this study, a RuS₂@CN-x photocatalyst with only exposed crystal face (200) was prepared by anchoring RuS₂ nanoparticles on carbon nitride (CN) nanosheets and successfully used in photocatalytic C–C bond cleavage of biomass-based sugars coupling with water splitting to co-generate lactic acid and hydrogen. Interestingly, the RuS₂ (200) crystal face combined with the interfacial synergism between CN and RuS₂ in RuS₂@CN-x effectively improved visible light absorption and enhanced the transfer/separation efficiency of photo-generated carriers. The RuS₂@CN-2 exhibited superior photocatalytic activity towards synchronous water splitting and biomass conversion to co-produce hydrogen (8698.3 μmol g⁻¹ h⁻¹) and lactic acid (91.5%). Furthermore, the experimental and DFT calculation results indicated that the exposed crystal face (200) of RuS₂ significantly enhanced the photocatalytic activity of RuS₂@CN-2. Moreover, this reaction system not only has excellent recyclability but also displays excellent universality for small molecule biomass-derived monosaccharides and macromolecular xylan. This work provides a novel route to efficiently co-produce hydrogen and fine chemicals from photocatalytic C–C bond cleavage of biomass coupling with H–O bond cleavage of water.