120th General Meeting of the KCS

Type Poster Presentation
Area Electrochemistry
Room No. Exhibition Hall 2+3
Time 10월 20일 (금요일) 13:00~14:30
Code ELEC.P-479
Subject Enhanced Electrocatalytic Reduction of CO2 to CO via Gold-Based Clusters
Authors Hoeun Seong, Yongjin Lee1, Dongil Lee1,*
Chemistry, Yonsei University, Korea
1Department of Chemistry, Yonsei University, Korea
Abstract As energy and environmental problem is being serious, electrochemical CO2 reduction reaction (CO2 RR) to value-added products is regarded as a useful method and becomes gradually notable in these days. Among the products to which CO2 can be reduced, CO has advantage to form a practical syngas with H2. However, efficient system for CO2 reduction to CO selectively has not been realized until now, because there are some problems such as complexity of CO2 RR and competition with hydrogen evolution reaction (HER). Herein, we use Au25(SC6H13)18 and Au38(SC6H13)24 nanoclusters as electrocatalysts with high selectivity for CO. The clusters are mixed with carbon black and nafion, and casted on gas diffusion layer. Constant potential electrolysis was then carried out for 1 hour, in aqueous solution containing KHCO3 and KCl. For Au25 cluster, the current density reaches up to 32mA/cm2 at -1.06V vs. RHE. For Au38 cluster, the current was found to be 42mA/cm2 at same potential, about 1.3 times higher than that of Au25, with maximum CO Selectivity of 97% at -0.86V. Moreover, electrolyte conditions that play an important role in CO2 reduction, higher current density and selectivity for CO were examined. Systematic investigations of the electrolyte compositions reveal that the bicarbonate concentration in the electrolyte profoundly affects the local and bulk pH, which control the catalytic activity and selectivity.
E-mail she6023@gmail.com