Constructing a Dual-Atom Catalyst Enables Electrocatalytic Synthesis of Urea by Coreduction of CO and N 2

Combining density functional theory calculations and a constant-potential model, the electrocatalytic performance for urea production on 3 homoatomic and 30 heteroatomic dual sites anchored on graphene (M 2 -N 6 @G and MM′-N 6 @G, M = Cr, Mo, and W, M′≠ M) was examined using N 2 and CO as feedstocks. The homoatomic catalysts encounter serious selectivity issues in that the formation of the intermediate of *NH 2 CHONH dominates over that of the targeting product *NH 2 CONH 2 due to a strong N adsorption strength. With the introduction of M′, MoFe-N 6 @G stands out from 30-plus candidates owing to its preference toward side-on adsorption of N 2 and unfavorable formation of *NH 2 CHONH. The high activity originates from a relatively weaker N adsorption, and the elusive selectivity is rooted in a moderate charge transfer from MM′ to N atoms. Our results underscore the role of adsorption strength of N in the electrocatalytic performance for urea production, offering a fundamental perspective for further optimizing the electrocatalysts.