Orbital Hybridization-Mediated Decoupling of Electrocatalytic Functions for Paired CO2 Electrosynthesis.

Abstract

The intrinsic trade-offs between activity, selectivity, and stability pose a fundamental challenge in electrocatalyst design. Here, we address these challenges by constructing a dual-scale catalytic architecture where traditionally competing functions are decoupled and optimized simultaneously. Our approach is guided by the unique orbital hybridization landscape of CeO₂ {110} facets, predicted by density functional theory (DFT) to confer a moderate Ag adsorption energy (-4.11 eV), to construct an electronically coupled interface of atomically dispersed Ag₁ (for CO₂ activation) and metallic Ag_n sub-nanoclusters (for electron transport). The resulting orbitally hybridized interface boosts oxygen vacancy (O_V) density by 1.84-fold and reduces charge-transfer resistance by 58%. When deployed in a membrane-free paired electrolyzer, this catalyst enables direct dialkyl carbonate synthesis from CO₂, achieving 88.53% Faradaic efficiency (FE) for dimethyl carbonate (DMC) at an industrial current density of 52.5 mA·cm^-2 with 20 h stability, a performance competitive with the state-of-the-art. The versatility of this morphology-governed orbital hybridization strategy is further demonstrated by the selective production of diethyl carbonate (DEC). This work establishes a rational design principle that controls catalytic synergy through crystallographically defined orbital interactions, offering a promising approach to address persistent trade-offs in electrocatalysis for CO₂ valorization.