Electrocatalytic Methane Oxidation to Ethanol via\nRh/ZnO Nanosheets

Abstract

The\ndirect conversion of methane to value-added chemicals at ambient\nconditions is a long-awaited perspective, and the electrocatalytic\nmethane oxidation reaction (CH₄OR) offers the potential\nof utilizing abundant natural gas and renewable energy sources. However,\ndue to the competition of water oxidation and the overoxidation of\nmethane, CH₄OR has remained as a significant challenge.\nIn this work, we developed Rh/ZnO nanosheets as an effective catalyst\nfor electrochemical conversion of methane into ethanol. The highly\ndispersed rhodium nanoparticles provided surface sites for methane\nadsorption, and ZnO allowed presentation of abundant active oxygen\nspecies for methane activation. With a 0.6% Rh doping ratio, the Rh/ZnO\nnanosheets demonstrated an excellent ethanol production rate of 789\nμmol·g_cat^–1·h^–1 at 2.2 V versus reversible hydrogen electrode, corresponding to\na Faradaic efficiency of 22.5% and an ethanol production selectivity\nof 85%, suggesting a promising means for methane utilization at ambient\nconditions.