Correlation of surface oxygen functional group with the iron reduction in MoO2-C/H2O2/Fe3+ system

Rational design and controllable synthesis of oxygen functional groups on carbon/metal catalysts surface as the effective means to enhance catalytic performance, however, still remains a great challenge. Herein, to obtain the relationship between oxygen functional groups and catalytic performance, taking MoO 2 -C as an object, the correlation between the C=O, C-O, Mo O bonds and strengthened iron reduction is quantitatively assessed, with electrochemical experiments validating that this relationship arises from its influence on the electron transport process, specifically concerning the roles of electron donors and mediators. The metal–oxygen and C-O bonds synergistically enhance electron transport, whereas the C=O and C-O bonds exhibit an antagonistic effect on electron-mediated processes. The influence of the metal–oxygen bonds was found to stem from their role as an electron donor, while the carbon–oxygen bonds primarily modulate the material’s catalytic properties by altering its electron transfer characteristics. In this study, the C-O, C=O bonds, and metal–oxygen bonds, as the typical surface oxygen functional groups, were identified the mechanism by changing the electron supply and mediation to enhance the Fe 3+ reduction reaction in the Fenton system, which provided theoretical support and design ideas for the design of catalyst with excellent catalytic properties.