Pauling-type adsorption of O2 induced electrocatalytic singlet oxygen production on N–CuO for organic pollutants degradation

Due to environmentally friendly operation and on-site productivity, electrocatalytic singlet oxygen ( 1 O 2 ) production via O 2 gas is of immense interest in environment purification. However, the side-on configuration of O 2 on the catalysts surface will lead to the formation of H 2 O, which seriously limits the selectivity and activity of 1 O 2 production. Herein, we show a robust N-doped CuO (N–CuO) with Pauling-type (end-on) adsorption of O 2 at the N–Cu–O 3 sites for the selective generation of 1 O 2 under direct-current electric field. We propose that Pauling-type configuration of O 2 not only lowers the overall activation energy barrier, but also alters the reaction pathway to form 1 O 2 instead of H 2 O, which is the key feature determining selectivity for the dissociation of Cu–O bonds rather than the O–O bonds. The proposed N dopant strategy is applicable to a series of transition metal oxides, providing a universal electrocatalysts design scheme for existing high-performance electrocatalytic 1 O 2 production.