Promotion effect of CO oxidation via activation of surface lattice oxygen by single atom Cu/MnO2 catalyst

Abstract

The catalytic oxidation of CO by single-atom transition metal catalysts has always been the focus of researchers. Herein, we report a strategy for the preparation of Cu single-atom anchored on MnO2 by oxalate chelation-assisted hydrothermal method, and the obtained Cu/MnO2–0.25 catalyst with the optimal molar ratio achieved about 90% CO conversion at 80 °C. The strong electronic interaction between Cu and MnO2 not only effectively inhibits the aggregation of Cu single atoms, but also the formed Cu-O-Mn hybrid structure activates the adjacent surface lattice oxygen, further improving the catalytic oxidation performance of CO at low and medium temperatures. The elevated activity is achieved at the single-atom active site by the Mars-van Krevelen (MvK) mechanism. This work provides a simple and reliable method for the rational design of stable transition metal single-atom catalysts and deepens the understanding of metal-support strong interactions (SMSI).