Porous Silver/Indium and Gold/Indium Electrocatalysts for Electrochemical Conversion of Carbon Dioxide

Tuesday, 3 October 2017
Prince George's Exhibit Hall D/E (Gaylord National Resort and Convention Center)
H. Lee (Chung-Ang University), H. Kim (Chung-Ang university), and S. H. Ahn (Chung-Ang University)
As the use of fossil fuels increased, the global warming is becoming much serious problem by huge emission of CO2 to atmosphere. Thus, tremendous efforts have been conducted to reduce the concentration of CO2 in atmosphere. As one of the promising technologies, the electrochemical conversion of CO2 to useful products has been received a great attention because these products are able to be utilized in various industrial fields. Among the products, the production of CO is known to have an economical benefit because the market price of CO is relatively higher than other products. As the electrocatalysts, the silver and gold-based metals are commonly used to produce CO from the electrochemical reduction of CO2. However, the cost is an important criterion for CO2 conversion although these noble metals are highly active and selective for CO production. In this study, the porous copper foam was fabricated by two-step galvanostatic electrodeposition in order to obtain a large electrochemical surface area, and then indium electrodeposition was carried out on the top of copper foam to suppress the hydrogen evolution reaction which is known as competitive reaction with electrochemical CO2 reduction. Then porous indium was immersed in the electrolytes which contained noble metals precursor in order to decrease the amount of noble metal usage. The fabricated porous silver/indium and gold/indium were used as electrocatalysts for the CO2 conversion reaction. The obtained CO Faradaic efficiency was varied by the material properties of silver/indium and gold/indium catalysts such as morphology, roughness and surface composition.