Manganese-doped molybdenum oxide boosts catalytic performance of electrocatalytic wet air oxidation at ambient...

Mn-doping strategy was adopted to modify the structure of MoO₂ for enhancing its catalytic activity towards room-temperature electrocatalytic wet air oxidation (ECWAO) reaction. A series of Mn-doped MoO₂ were prepared on carbon support, and their structures were investigated to elucidate the productive effect of Mn doping on the catalytic activity of MoO₂. The incorporation of Mn^III/Mn^II into the MoO₂ lattice induced the transformation from Mo^IV to Mo^V and created more oxygen vacancies. Such structural modifications promoted the electron transfer of MoO₂ through the redox couples between Mo^VI/Mo^V/Mo^IV and Mn^III/Mn^II, and facilitated the transformation from O₂ to adsorbed oxygen species on MoO₂ surface. As a result, the ECWAO catalytic activities of Mn-doped MoO₂/graphite felt (MoO₂/GF) outperformed the activity of MoO₂/GF. Among the synthesized series, Mn_0.066:MoO₂/GF exhibited the highest activity with the maximum turnover frequency (TOF) promoted by 59% than the undoped MoO₂/GF. Under the catalysis of Mn_0.066:MoO₂/GF, the ECWAO process obtains mineralization efficiencies generally above 85% in degrading typical pharmaceutics and person care products (PPCPs). These findings are anticipated to open up a new venue in the design and fabrication of highly active catalysts for air oxidation reactions by using the strategy of selective dopant-induced structure modification.