Fabrication of Hollow-shape CuO Nanoparticle Assembly with Sacrificial W18O49 Template for C2+-Product-Selective Electrochemical CO2 Reduction

Abstract

Tungsten suboxide (W18O49) was used as a sacrificial template to prepare hollow-shape assembly of CuO nanoparticles as an active and stable catalyst for electrochemical CO2 reduction. Catalyst precursor materials Cu-W18O49-x’s (x denotes the amount of Cu added; x = 0.1, 0.2, 0.5, 1, 2) were prepared by deposition of single-atomic Cu species on the surface of W18O49. In alkaline electrolyte, the W18O49 phase gradually dissolved and the single-atomic Cu sites aggregated into ultrasmall CuO particles with average sizes of 5-10 nm, which further formed hollow-shape assembly with high surface areas. The CuO nanoparticle assembly was found a good catalyst for selective CO2 reduction to C2+ products such as ethylene and ethanol with Faraday efficiency up to 58% and partial current density up to 167 mA/cm2.