Spatially asymmetrical copper dimer in ceria as an efficiently synergistic oxidation catalyst

Accurate and facile construction of atomically dispersed active sites is fundamentally important in heterogeneous catalysis. Herein, by applying a unique H₂-He pretreatment, we successfully synthesize spatially asymmetrical dimeric Cu stabilized by CeO₂. Integrated microscopic and spectroscopic characterizations, together with DFT calculations have revealed the redispersion of Cu species on CeO₂ support is accompanied by the formation of Cu dimers with one Cu atom embedded into CeO₂ lattice and the neighboring Cu atom supported on-top. The obtained dual-Cu atom catalyst demonstrates its general applicability in emission control scenarios or hydrogen fuel cell for automobile applications with excellent performances. Ab initio calculations reveal that such dimeric Cu sites on CeO₂ promote reactant adsorption and lattice oxygen activation, owing to the synergistic effect of unique dimeric Cu structure. This work highlights the great potential of gas pretreatment in the fabrication of dual-atom catalysts, which is widely applicable to active site modulation in advanced oxidation catalysts.