A 2D Porous Cu3N Catalyst for Efficient CO Electroreduction to Multicarbon Products at an Ampere Level Current Density

Abstract The maturation of CO 2 electrolysis to CO technology has rendered a cascade catalysis scheme, utilizing CO reduction as a media step, a promising strategy to produce high‐value C 2+ fuel. However, the current catalysts employed in CO electroreduction (ECORR) face severe hydrogen evolution reactions at high current densities. Herein, a 2D porous Cu 3 N (2D‐P‐Cu 3 N) catalyst is reported with outstanding ECORR performance prepared by a two‐step pyrolysis strategy. This strategy mainly relies on the sequential annealing of the Cu 2 (OH) 2 CO 3 precursors in an oxidation and reduction atmosphere, which can not only convert it into high‐purity Cu 3 N, but also endow it with an abundant hierarchical pores structure. The pores can significantly improve the in‐plane conductivity and mass transfer capacity of Cu 3 N, enabling a C 2+ faradaic efficiency exceeding 90% at a current density of 0.6 A cm −2 . Even at an ampere grade current density of 1 A cm −2 , it maintains an impressive 87% selectivity, surpassing most of the reported Cu‐based catalysts. In‐situ Raman spectroscopy confirms that 2D‐P‐Cu 3 N exhibits high coverage and adsorption of CO intermediates, thus enhancing C‐C coupling and promoting the generation of C 2+ products. This discovery opens further exploration of catalysts for selective CORR to C 2+ products.