Unveiling the tailorable catalytic surface properties of ceria-promoted cobalt binary spinel catalysts for efficient N2O direct decomposition

Abstract

Spinel-type oxides based on transition metals are a specific class of catalysts that have recently been highly regarded as active sites for enhancing N2O direct decomposition. The catalytic performance of CoxCey binary spinel catalysts was compared to that of single Co and Ce oxide catalysts. The Co2Ce1 binary spinel catalyst exhibited superior N2O decomposition performance, achieving over 95 % N2O conversion at GHSV of 60,000 h？1 and 300 °C. Physicochemical analysis revealed that the Co2Ce1 catalyst possessed the smallest particle size and the largest surface area, with Co occupying octahedral sites of Co spinel. Additionally, Ce weakened the Co？O bond and introduced abundant surface oxygen vacancies, basicity, and facilitated Co2+ and Ce3+ interactions on the catalyst surface. Furthermore, the number of Lewis acid sites emerged as a critical factor in N2O decomposition. The Co2Ce1 catalyst demonstrated promising potential for efficient N2O decomposition at lower temperatures.