In situ oxidative etching-enabled synthesis of hollow Cu2O nanocrystals for efficient CO2RR into C2+ products

The prepared hollow Cu 2 O nanocrystals via oxidative etching yield C 2+ products with a faradaic efficiency of 75.9% and a C 2+ partial current density of 0.54 A cm −2 ascribed to their defect-rich sites and abundant stepped facets.