Hollow Hierarchical Cu<sub>2</sub>O‐Derived Electrocatalysts Steering CO<sub>2</sub> Reduction to Multi‐Carbon Chemicals at Low Overpotentials
Jinhan Li, Keqiang Xu, Fangming Liu, Youzeng Li, Yanfang Hu, Xijie Chen, Huan Wang, Wence Xu, Youxuan Ni, Guoyu Ding, Tete Zhao, Yu Meng, Wei Xie, Fangyi Cheng
Abstract
Abstract The electrochemical reduction of carbon dioxide into multi‐carbon products (C 2+ ) using renewably generated electricity provides a promising pathway for energy and environmental sustainability. Various oxide‐derived copper (OD‐Cu) catalysts have been showcased, but still require high overpotential to drive C 2+ production owing to sluggish carbon–carbon bond formation and low CO intermediate (*CO) coverage. Here, the dilemma is circumvented by elaborately devising the OD‐Cu morphology. First, computational studies propose a hollow and hierarchical OD‐Cu microstructure that can generate a core–shell microenvironment to inhibit CO evolution and accelerate *CO dimerization via intermediate confinement and electric field enhancement, thereby boosting C 2+ generation. Experimentally, the designed nanoarchitectures are synthesized through a heteroseed‐induced approach followed by electrochemical activation. In situ spectroscopic studies further elaborate correlation between *CO dimerization and designed architectures. Remarkably, the hierarchical OD‐Cu manifests morphology‐dependent selectivity of CO 2 reduction, giving a C 2+ Faradaic efficiency of 75.6% at a considerably positive potential of −0.55 V versus reversible hydrogen electrode.