Constructing efficient CuOx-CeO2 catalyst for NO reduction by CO: New insights into the structure-activity relationship

CuO-CeO2 based materials have been recognized as promising substitutes for precious metal catalysts in emission control field due to their superior redox property and low cost. Herein, by optimizing the deposition process of CeO2 and CuO onto gamma-Al2O3, highly dispersed CuO clusters on unique CeO2-Al2O3 support with small CeO2 particles (7Cu-Ce/CeAl) were successfully constructed for efficient NO reduction by CO, which exhibited much higher NO removal efficiency and N2 selectivity than CuO catalysts supported on gamma-Al2O3 (7Cu/Al) and con-ventional CeO2-Al2O3 support (7Cu/CeAl). Moreover, H2O showed limited inhibition effect on the catalytic performance of 7Cu-Ce/CeAl catalyst. With the help of Raman spectra, X-ray absorption spectroscopy, in situ diffuse reflectance infrared Fourier transform spectroscopy, etc., it was clearly revealed that the abundant Cu+/ Ce3+ paired sites with surface synergetic oxygen vacancies (SSOV) on 7Cu-Ce/CeAl catalyst could effectively facilitate the adsorption and activation of CO and NO, thus significantly enhancing the NO removal efficiency.

Automated summary

By optimizing the deposition process, highly dispersed CuO clusters on unique CeO2-Al2O3 support with small CeO2 particles were successfully constructed, which exhibited much higher NO removal efficiency and N2 selectivity compared to CuO catalysts supported on gamma-Al2O3 and conventional CeO2-Al2O3 support. H2O showed limited inhibition effect on the catalytic performance of the catalyst. The abundant Cu+/Ce3+ paired sites with surface synergetic oxygen vacancies on the catalyst effectively facilitated the adsorption and activation of CO and NO, thus significantly enhancing the NO removal efficiency.