Facile Synthesis of Nanostructural High-Performance Cu–Pb Electrocatalysts for CO2 Reduction

Nanostructure and crystallinity of transition metals play an important role in catalyzing carbon dioxide electroreduction (CO 2 ER) where Cu is a typical electrocatalyst with a wide variety of products and Pb has a high overpotential for H 2 evolution and is selective toward formic acid. In this study, 3D hierarchical nanostructures of Cu–Pb catalyst are prepared by a two-step electrodepositing–annealing–electroreduction approach (EAE). Cu nanowires (Cu NWs) of 200–400 nm diameter are built on the surface of commercial nickel foam substrates through an EAE step. Then, Pb nanoparticles with diameter of 5–10 nm are uniformly created on the surface of Cu NWs by a second EAE step. The nanostructural Cu–Pb electrodes catalyze CO 2 ER at a current density of −9.35 mA cm −2 (at −0.93 V vs reversible hydrogen electrode (RHE)). The H 2 evolution is suppressed by 35.6% and CO and HCOOH are enhanced by 29.6% and 9.2%, respectively, as compared with Cu NWs. The protocol proposed in this study provides a simple and straightforward approach for preparing high-performance, hierarchical nanostructures of Cu–Pb bimetal catalyst for CO 2 ER.