Disordered interfacial hydrogen-bond networks enhance selective ethylene production under ampere-level CO₂ electroreduction

Engineering the hydrogen-bond network is essential for enhancing multicarbon (C₂₊) formation during electrochemical CO₂ reduction. However, rational regulation of the hydrogen-bond network by modifying the interfacial water microenvironment remains a great challenge. Here, we develop an atomically dispersed Gd doped Cu₂O that could attract H₂O molecules and weaken O–H bonding, thereby facilitating water dissociation and providing sustained *H. The as-prepared catalyst achieved a maximum Faradaic efficiency of 63.5% for C₂H₄ at an industrial current density of −1000 mA cm⁻². In situ spectroscopies reveal a substantial increase in the proportion of free-H₂O species and a more disordered interfacial hydrogen-bond network upon Gd doping, which could modulate the *H transfer kinetics and suppress the hydrogen evolution reaction. Theoretical calculations confirm that the atomically dispersed Gd can modulate the interfacial water microenvironment, strengthen *CO₂ adsorption and promote the asymmetric *CO–*CHO coupling. This work establishes atomic-level rare-earth doping as a powerful strategy that achieves selective C₂₊ production by engineering the interfacial water microenvironment.