Carbon-Supported Ni–Cu Bimetallic Nanoparticle Materials for Highly Efficient Electrocatalytic Conversion of CO2 to CO

Abstract

Electrocatalytic reduction of carbon dioxide is a highly effective method for energy storage. It is essential to explore inexpensive metal catalysts that exhibit high selectivity and yield for carbon monoxide, yet this remains a significant challenge. In this study, carbon-supported Ni–Cu bimetallic nanoparticles (denoted as Ni_xCu_y NPs-C) are synthesized through low-temperature carbonization of Ni_xCu_y-ZIF. The carbon matrix effectively prevents the aggregation of Ni/Cu NPs, allowing for a more uniform dispersion that exposes a greater number of active sites. The well-conductive Ni/Cu particles facilitate electron transfer, contributing to high current density. Electrocatalytic performance tests indicate that the synthesized catalyst can efficiently convert carbon dioxide to carbon monoxide, achieving a Faradaic efficiency for CO (FE_CO) exceeding 90% at potentials from −0.9 V (vs. reversible hydrogen electrode (RHE)) to −1.1 V (vs. RHE), with a peak FE_CO of 96.37 % at −1.1 V (vs. RHE) and a total current density of 15.435 mA cm⁻².