Reinventing MoS2 Co-catalytic Fenton reaction: Oxygen-incorporation mediating surface superoxide radical generation

To better understand the mechanisms of hydrogen peroxide (H 2 O 2 )’s decomposition and reactive oxygen species (ROS)’s formation on the catalyst’s surface is always a critical issue for the environmental application of Fenton/Fenton-like reaction. We here report a new approach to activate H 2 O 2 in a co-catalytic Fenton system with oxygen incorporated MoS 2 , namely MoS 2− x O x nanosheets. The MoS 2− x O x nanosheets assisted co-catalytic Fenton system exhibited superior degradation activity of emerging antibiotic contaminants (e.g., sulfamethoxazole). Combining density functional theory (DFT) calculation and experimental investigation, we demonstrated that oxygen incorporation could improve the intrinsic conductivity of MoS 2− x O x nanosheets and accelerate surface/interfacial charge transfer, which further leads to the efficacious activation of H 2 O 2 . Moreover, by tuning the oxygen proportion in MoS 2− x O x nanosheets, we are able to modulate the generation of ROS and further direct the oriented-conversion of H 2 O 2 to surface-bounded superoxide radical (·O 2 surface − ). It sheds light on the generation and transformation of ROS in the engineered system (e.g., Fenton, Fenton-like reaction) for efficient degradation of persistent pollutants.