Dual-Metal Hetero-Single-Atoms with Different Coordination for Efficient Synergistic Catalysis

Abstract

Rationally tailoring the coordination environments of metal single atoms (SAs) is an effective approach to promote their catalytic performances, which, however, remains as a challenge to date. Here, we report a novel misplaced deposition strategy for the fabrication of differently coordinated dual-metal hetero-SAs. Systematic characterization results imply that the as-synthesized dual-metal hetero-SAs (exemplified by Cu and Co) are affixed to a hierarchical carbon support via Cu-C₄ and Co-N₄ coordination bonds. Density functional theory studies reveal that the strong synergistic interactions between the asymmetrically deployed CuC₄ and CoN₄ sites lead to remarkably polarized charge distributions, i.e., electron accumulation and deficiency around CuC₄ and CoN₄ sites, respectively. The obtained CuC₄/CoN₄@HC catalyst exhibits significantly enhanced capability in substrate adsorption and O₂ activation, achieving superior catalytic performances in the oxidative esterification of aromatic aldehydes in comparison with the Cu- and Co-based SA counterparts.