Visible-Light-Driven Valorization of Biomass Intermediates Integrated with H_2 Production Catalyzed by Ultrathin Ni/CdS Nanosheets

摘要

Photocatalytic upgrading of crucial bio-mass-derived intermediate chemicals (i.e., furfural alcohol, 5-hydroxymethylfurfural (HMF)) to value-added products (aldehydes and acids) was carried out on ultrathin CdS nanosheets (thickness ~1 nm) decorated with nickel (Ni/ CdS). More importantly, simultaneous H_2 production was realized upon visible light irradiation under ambient conditions utilizing these biomass intermediates as proton sources. The remarkable difference in the rates of transformation of furfural alcohol and HMF to their corresponding aldehydes in neutral water was observed and investigated. Aided by theoretical computation, it was rationalized that the slightly stronger binding affinity of the aldehyde group in HMF to Ni/CdS resulted in the lower transformation of HMF to 2,5-diformylfuran compared to that of furfural alcohol to furfural. Nevertheless, photo-catalytic oxidation of furfural alcohol and HMF under alkaline conditions led to complete transformation to the respective carboxylates with concomitant production of H_2.