Electrochemical reduction of carbon dioxide on nanostructured catalysts

Abstract

There is great interest in the conversion of carbon dioxide (CO2) to useful chemicals and fuels toward addressing the increasingly serious impacts of global climate change. The electrochemical reduction of CO2 has garnered keen and broad interest due to the development of efficient electrocatalysts. In this thesis I initially demonstrated a facile approach for the synthesis of a novel nanostructured thin film comprised of Cu nanoparticles (NPs) and reduced graphene oxide (rGO) on a glassy carbon electrode (GCE), via the direct electrochemical reduction of a mixture of copper and graphene oxide (GO) precursors. The effects of an applied potential on the electrochemical reduction of CO2 was investigated using linear sweep voltammetric (LSV) and chronoamperometric (CA) techniques. Carbon monoxide (CO) and formate were found as the primary products based on gas chromatograph (GC) and high performance liquid chromatography (HPLC) analysis. The electrochemical reduction of CO2 at the Cu/rGO thin film was further studied using in situ electrochemical ATR-FTIR spectroscopy to identify the liquid products that were generated at different applied cathodic potentials. Our experimental measurements revealed that the nanostructured Cu/rGO thin film exhibited excellent stability and superb catalytic activity for the electrochemical reduction of CO2 in an aqueous solution, with a high current efficiency of 69.4% at -0.6 V vs. RHE.