Copper rhodium nanosheet alloy for electrochemical NO reduction reaction via selective intermediate adsorption

Abstract

Electrochemical nitric oxide reduction reaction (eNORR) is regarded a promising strategy for NO removal and NH₃ synthesis. However, current electrocatalysts for NORR encounter problems of low activity and selectivity, also facing the challenge of avoiding competitive hydrogen evolution reaction (HER). Herein, we designed and fabricated CuRh metal alloy nanosheets based on a facile solvothermal method for selective NH₂OH* adsorption in eNORR. In situ FTIR spectroscopy revealed that the CuRh nanosheets (CuRh NSs) enhanced the adsorption of NH₂OH*, thus promoting the generation of NH₄⁺. CuRh NSs exhibited efficient NORR catalysis with a high faradaic efficiency (FE) of 93.1% and an ammonia yield of 436 μmol h⁻¹ cm⁻² at −0.6 V vs. RHE. Our work demonstrated that the introduction of Rh could regulate the electronic structure of Cu in CuRh NSs, optimizing its adsorption ability towards NH₂OH*, and improving the catalytic selectivity for ammonia synthesis via eNORR.