Selectively catalytic conversion H2O into singlet oxygen (1O2) without additional oxidants is considered as an economic-efficient method for organic pollutants degradation. However, H2O are more consistent with the spin state of 1O2 than common oxygen (O2), retarding the kinetics of spin transition-induced reaction between O2 and 1O2. Herein, we report an unprecedented 1O2 mediated electrocatalytic oxidation process, which allows O–O coupling for 1O2 evolution from H2O over CrMn@C anode. The electron occupancy (eg) of CrMn@C (0.89) is very close to the optimal eg (0.95) of manganese-based materials reported in the literature, which facilitates the activation of H2O on surface. Mn(Mn0.193Cr1.808)O4-Mn in CrMn@C electrode significantly promotes the activation of H2O to produce *O, followed by coupling of *O at adjacent sites to produce *OO, which further spontaneously forms 1O2. And H218O isotope experiments provide direct evidence for the production of 1O2 directly from H2O. Consequently, the production of 1O2 is enhanced with the yield of 785.6 μmol·L−1. Such 1O2-dominated electrocatalytic oxidation system can achieve efficient removal of electron-rich pollutant (bisphenol A) and improve the biodegradability of pharmaceutical wastewater (from 0.17 to 0.39).
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