Facile Synthesis of Thiol-Decorated Ag Nanoparticles as Electrocatalyst for CO2RR

Large amount of traditional fossil fuels has been consumed as energy resource with inevitably emitted carbon dioxide (CO2), one of the greenhouse gases, resulting in the global warming. Electrochemical catalysis is a cost-effective and energy-efficient way to convert CO2 into valuable products under ambient condition. However, the electrocatalytic reaction involved various pathways suffers from low selectivity and high overpotentials. Therefore, developing the electrocatalysts with the high selectivity and low overpotentials has been the focus of research.<br/>Efficient carbon dioxide reduction reactions (CO2RR) is required to reduce greenhouse gases and obtain useful carbonaceous chemicals. Electrochemical carbon dioxide reduction (ECR) is one of the most effective methods to reduce carbon dioxide to carbon monoxide and/or other valuable chemicals. Coinage metals, i.e., gold, silver, and copper, are known as catalytic materials for ECR due to their appropriate binding energy for the intermediates (*COOH or *CO ). Among them, silver-based catalysts showed high selectivity with relatively low overpotential and low cost. Morphology modification, size engineering and alloying have been conducted to improve ECR performance by promoting the reaction kinetics and selectivity. However, ECR can be improved by not only the enhancement of intrinsic activity but also extrinsic modification of interface.<br/>Molecule-mediated electrocatalysts have been attracted attentions due to their unique electrochemical properties on interface between molecule and surface of electrocatalysts. The molecules around the electrocatalyst could adjust the electronic states of the surface resulting in improved activity and products selectivity. Conventional bulk metal electrodes after the modification of surface of electrodes by molecules showed enhanced ECR performance. We designed and fabricated a Thiol-decorated silver (Ag) nanoparticles on carbon support via simple acid reduction method. The as-prepared electrocatalyst has good dispersion and uniformity in particle size.