Sustainable H2 Production from Lignocellulosic Biomass over MoS2 Modified Sulfur Vacancy Enriched ZnIn2S4 Photocatalyst

Exploring visible-light-responsive photocatalysts for photocatalytic lignocellulosic biomass-to-H₂ conversion remains a glamorous but challenging goal because the photogenerated holes cannot directly transfer to biomass owing to the absence of a charge transfer channel. Herein, we design ZnIn₂S₄ nanosheets with abundant sulfur vacancy (V_S-ZnIn₂S₄) as visible light responsive photocatalysts for photocatalytic H₂ production from lignocellulosic biomass in the presence of MoS₂ as the cocatalyst. In this smartly designed photocatalysts, the sulfur vacancy in ZnIn₂S₄ reduces the energy barrier of ^•OH generation reaction and results in the fast dynamics for the generation of ^•OH, which acts as the crucial species for the oxygenolysis of lignocellulosic biomass. As expected, the H₂ generation rate of the optimized MoS₂/V_S-ZnIn₂S₄ photocatalyst in α-cellulose and bamboo powder aqueous solution achieves 1572 and 133 μmol·g^–1·h^–1, respectively. This study validates the feasibility of sulfur vacancy to boost visible light photocatalytic conversion of lignocellulosic biomass into H₂ fuel.