Efficient acceptorless dehydrogenation of 5-Hydroxymethylfurfural (HMF) to 2,5-Diformylfuran (DFF) over Pt/CdS under visible light

The selective transformation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF) with coproduction of hydrogen under visible light is appealing yet still challenging. In this manuscript, Pt/CdS nanocomposites obtained via photoreduction of [PtCl6]2- over CdS were found to be an efficient and chemoselective photocatalyst for dehydrogenation of HMF to produce DFF under visible light, with simultaneously generation of stoichiometric hydrogen. An optimum performance was observed over 1.0 wt% Pt/CdS nanocomposite, with a complete conversion of HMF to DFF and stoichiometric hydrogen generated in 14 h. By comparison with the performance over MoS2/CdS, it is revealed that the superior performance for photocatalytic dehydrogenation of HMF over Pt/CdS should be ascribed to the strong interaction between the furan ring in HMF with Pt nanoparticles (NPs), which enables the protons released from HMF to fast transfer to Pt NPs in close vicinity for further reduction to generate hydrogen. This study provides an efficient and green strategy for the simultaneous transformation of biomass-derived HMF to DFF and the production of clean energy hydrogen. This work also highlights the great potential of photocatalysis in biomass valorization.