Innovative one-step hydrothermal fabrication of MoS2/ZnIn2S4 heterojunction for efficient visible photocatalytic oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran

A MoS 2 /ZnIn 2 S 4 composite photocatalyst were synthesized via a one-step hydrothermal method for the visible-light-driven oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF). The reaction was conducted under mild, environmentally friendly conditions, using water as the solvent and without the need for additional oxidizing agents. The flower-like MoS 2 /ZnIn 2 S 4 structure exhibited a high specific surface area, and the formation of a Z -scheme heterojunction between MoS 2 and ZnIn 2 S 4 effectively suppressed the recombination of photogenerated electron-hole pairs, thereby enhancing photocatalytic performance. Density functional theory (DFT) calculations revealed that the 17.5 % MoS 2 /ZnIn 2 S 4 composite possessed lower adsorption energy and a more delocalized electron cloud, creating more favorable conditions for HMF oxidation. Under optimal conditions, the catalyst achieved 70.2 % conversion of HMF with 92.2 % selectivity toward DFF after 3 h of xenon light irradiation. Radical trapping experiments indicated that superoxide radical (•O 2 − ) were the dominant reactive species driving the transformation. This study highlights the potential of one-step hydrothermally synthesized Z -scheme MoS 2 /ZnIn 2 S 4 heterojunctions for efficient biomass-derived chemical valorization, offering valuable insights for the sustainable production of DFF and related high-value chemicals.