Nitride‐Derived Copper Modified with Indium as a Selective and Highly Stable Catalyst for the Electroreduction of Carbon Dioxide

The lack of efficient catalysts prevents the electrocatalytic reduction of carbon dioxide from contributing to the pressing target of a carbon‐neutral economy. Indium‐modified copper nitride was identified as a stable electrocatalyst selective toward CO. In(2)O(3)/Cu(3)N showed a Faradaic efficiency of 80 % at 0.5 V overpotential for at least 50 h, in stark contrast to the very limited stability of the benchmark In(2)O(3)/Cu(2)O. Microfabricated systems allowed to correlate activity with highly stable interfaces in indium‐modified copper nitride. In contrast, fast diffusion of indium resulted in rapidly evolving interfaces in the case of the system based on oxide‐derived Cu. A metastable nitrogen species observed by spectroscopic means was proposed as the underlying cause leading to the unchanging interfaces. This work reveals the stabilizing properties of nitride‐derived copper toward high‐performance multicomponent catalysts.