In situ growth of Cu-modified oxynitride for optimized photocatalytic nitric oxide oxidation.

Photocatalysis technology provides a promising and green strategy for the abatement of low-concentration NO pollutants in the ambient air. An earthworm-like oxynitride decorated with in situ grown Cu nanoparticles is synthesized through the ammonolysis of the CuO-doped ZnGaO spinel. The optimized morphology promoted the exposure of active sites and expanded the reaction interface for efficient NO adsorption and photocatalytic conversion. The decoration of Cu and N doping enhanced the light absorption and imparted a tunable energy band structure. The strong interactions between Cu and the GaZnNO interface maximize the utilizing photo-induced charge by facilitating the transfer and inhibiting the recombination of the charge carrier. The strong adsorption of HO and NO on Cu and internal electric field of Cu-GaZnNO junction contribute to the high selectivity of NO. This study provides a new perspective on the design of visible-light-driven photocatalysts with Schottky junction for environmental remediation.