Modifying Pathways in CO Preferential Oxidation over CuxO/CeO2 Catalysts by Boosting Cu-Ce Interfacial Interaction

Improving the dispersion of CuxO species is critical for enhancing the catalytic performance of CuxO/CeO2 catalysts in the preferential oxidation of CO. Herein, the 10CuxO/CeO2 catalyst was synthesized using a combined approach of one-step thermal decomposition and precipitation methods. A series of characterization results indicate that the CeO2 support we prepared is rich in defect sites, which not only enhance the interaction between CeO2 and CuxO, but also promote the generation of more active Cu+ sites while reducing the strength of the Ce−O bond. Raman spectroscopy and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) demonstrated that the weakened Ce–O bonds promote the extraction of lattice oxygen, thereby enhancing the carboxyl reaction pathway. Consequently, the highly dispersed 10CuxO/CeO2 catalyst exhibits remarkably high catalytic activity for the oxidation of CO over a broad operating temperature range (i.e., CO 100% conversion, 95–215 °C). This study represents an important advancement toward the facile synthesis of highly active transition-metal oxide catalysts.