CuSn Alloy Nanoparticles on Nitrogen‐Doped Graphene for Electrocatalytic CO2 Reduction

Abstract

AbstractWe report an efficient electrocatalyst utilizing non‐noble metals consisting of Cu and Sn supported on nitrogen‐doped graphene (NG) for reduction of CO2 over a wide potential range. The CuSn alloy nanoparticles (NPs) on NG were prepared through a hydrothermal method followed by pyrolysis under nitrogen atmosphere to achieve a uniform dispersion of the alloy NPs. The CuSn NP (Cu/Sn ratio of 0.175) decorated NG catalyst performed electrocatalytic reduction of CO2 into C1 products at a Faradaic efficiency (FE) of nearly 93 % at an overpotential of −1.0 V vs. RHE, considerably higher than that of the Cu and Sn counterparts, i. e., 32 % and 58 %, respectively. The enhanced catalytic activity could be attributed to the collaboration between the CuSn alloy and Sn metal. The first‐principles density functional theory (DFT) simulation results indicate that the CuSn bimetal alloy nanoparticles enable more H atoms to participate in the electrocatalytic reduction of CO2 and exhibit an improved CO2 capture performance. In addition, the CuSn alloy having a lower barrier than that of Sn metal can accelerate the CO2 reduction process. This study presents the strategy that utilizes low‐cost non‐noble metals as highly efficient electrocatalysts for aqueous reduction of CO2.