ZnS-embedded porous carbon for peroxydisulfate activation: Enhanced electron transfer for bisphenol A degradation

Transition metal sulfides have garnered increasing attention for their role in persulfate activation, a crucial process in environmental remediation. However, the function of metal sulfides without reversible valence changes, such as ZnS, remains largely unexplored in this context. Here we report ZnS-embedded porous carbon (ZnS-C), synthesized through the pyrolysis of Zn-MOF-74 and dibenzyl disulfide. ZnS-C demonstrates remarkable activity in activating peroxydisulfate (PDS) across a wide pH range, enabling the efficient mineralization removal of bisphenol A (BPA). Through electrochemical investigation and theoretical simulations of charge density distributions, we unveil that the electron transfer from BPA to PDS mediated by the ZnS-C catalyst governs the reaction. This study, both in theory and experiment, demonstrates metal sulfide as electron pump that enhances electron transfer efficiency in PDS activation. These findings redefine the role of metal sulfide catalysts, shedding new light on their potential for regulating reaction pathways in PDS activation processes

Highly-efficient photocatalytic H2O2 evolution using hydrothermal carbons with donor-acceptor furan couples

Nature-inspired photosynthesis of H2O2 using sustainable catalytic materials is promising to generate high-value chemicals and solar fuels from renewable energy sources. However, existing H2O2 evolution systems still face limitations of low efficiency, high cost, and the need for sacrificial agents or organic electron donors. Herein, we report novel furan-resin-structured hydrothermal carbons (HTCs) as photocatalytic H2O2 generation catalysts by one-step hydrothermal carbonization of saccharides or biomass. The catalysts have high production efficiency (480.7 μmol gcat−1 h−1) for photocatalytic H2O2 evolution without any sacrificial agent or O2 aeration. This is one of the pioneer studies of HTCs constructed by low-bandgap furan resin comprising conjugated quinoid and aromatic furan units. The underlying mechanism is based on the π-stacked donor-acceptor (D-A) furan couples that significantly enhance the charge transfer efficiency of photogenerated electrons. The reported low-cost and easy-to-manufacture HTC photocatalysts with remarkable activity show great potential in artificial photosynthesis applications.</p