Manipulating local coordination of copper single atom catalyst enables efficient CO(2)-to-CH(4) conversion

Electrochemical CO(2) conversion to methane, powered by intermittent renewable electricity, provides an entrancing opportunity to both store renewable electric energy and utilize emitted CO(2). Copper-based single atom catalysts are promising candidates to restrain C-C coupling, suggesting feasibility in further protonation of CO* to CHO* for methane production. In theoretical studies herein, we find that introducing boron atoms into the first coordination layer of Cu-N(4) motif facilitates the binding of CO* and CHO* intermediates, which favors the generation of methane. Accordingly, we employ a co-doping strategy to fabricate B-doped Cu-N(x) atomic configuration (Cu-N(x)B(y)), where Cu-N(2)B(2) is resolved to be the dominant site. Compared with Cu-N(4) motifs, as-synthesized B-doped Cu-N(x) structure exhibits a superior performance towards methane production, showing a peak methane Faradaic efficiency of 73% at −1.46 V vs. RHE and a maximum methane partial current density of −462 mA cm(−2) at −1.94 V vs. RHE. Extensional calculations utilizing two-dimensional reaction phase diagram analysis together with barrier calculation help to gain more insights into the reaction mechanism of Cu-N(2)B(2) coordination structure.