Enhanced catalytic performance and N2 yield of Ag/CeO2 catalyst by Cu modification for NVOCs removal

5 wt% Ag/CeO2 nanorods catalyst possesses exceptional activity in catalytic oxidation of N, N-Dimethylformamide (DMF), however, its N2 yield is relatively low. To modify the catalytic activity and N2 yield, Cu species were introduced to prepare a series of 5AgxCu/CeO2 catalysts (x = 0, 1, 5, 10) by conventional incipient wetness impregnation method. Among all catalysts, 5Ag5Cu/CeO2 catalyst exhibited the best activity (T90 = 160 °C), the lowest complete oxidation temperature of organic intermediates (Tc = 240 °C) and tremendous stability under both dry and humid conditions. More importantly, N2 yield of 5Ag5Cu/CeO2 catalyst enhanced significantly from less than 80 % to 90 %, in comparison to the 5Ag0Cu/CeO2 catalyst. According to characterization results, well-dispersed CuO species and Cu-O-Ce interfaces provided abundant active oxygen species, thus improving the activity of catalytic oxidation of DMF and organic intermediates. Besides, the introduction of Cu species also promoted the oxidation of NO, and the generation of NO2 benefitted N2 yield through fast SCR reaction with organic reactant and intermediate. In addition, the interaction between Ag species and CeO2 support was also weakened after introduction of Cu species. Subsequently, metallic Ag0 particles dominated the 5Ag5Cu/CeO2 catalyst and enhanced the SCR performance, thus effectively increasing N2 yield.