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

Due to environmentally friendly operation and on-site productivity, electrocatalytic singlet oxygen (O) production via O gas is of immense interest in environment purification. However, the side-on configuration of O on the catalysts surface will lead to the formation of HO, which seriously limits the selectivity and activity of O production. Herein, we show a robust N-doped CuO (N-CuO) with Pauling-type (end-on) adsorption of O at the N-Cu-O sites for the selective generation of O under direct-current electric field. We propose that Pauling-type configuration of O not only lowers the overall activation energy barrier, but also alters the reaction pathway to form O instead of HO, 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 O production.