Co Single Atoms and CoOx Nanoclusters Anchored on Ce0.75Zr0.25O2 Synergistically Boosts the NO Reduction by CO

Abstract

AbstractAchieving high NO conversion and N2 selectivity in selective catalytic reduction of NO by CO (CO‐SCR) in a wide operating temperature window, particularly in the presence of high O2 concentration, remains a big challenge. Herein, guided by density functional theory (DFT) calculations, a catalyst is rationally developed with dual active centers consisting of both Co single‐atoms (SAs) and CoOx nanoclusters (NCs) co‐anchored on Ce0.75Zr0.25O2 support (CZO), which show above 99.7% NO conversion and 100% N2 selectivity at 250–400 °C under 5 vol% O2. DFT calculation and experimental results confirm a strong interaction among Co SAs, CoOx NCs, and CZO support. Co SAs enhance CO adsorption and accompany the oxygen vacancies (OVs) formation in CZO, while the CoOx NCs promote both NO conversion to nitrate intermediate and the breakage of the NO bond at OVs, thus synergistically boosting the N2 formation.