Silver-Based Catalytic Materials Prepared via Electrochemical Reconstruction for Efficient Carbon Dioxide Reduction

Abstract

Silver-based catalytic materials have garnered considerable attention due to their high selectivity towards carbon monoxide (CO) in the electrochemical reduction (ECR) of CO₂. However, the fabrication of silver-based ECR catalysts with high product selectivity and low competitive reaction activity using facile methods remains challenging. This study employed in situ electrochemical reconstruction to design high-performance silver-based catalytic materials for ECR, exploring performance enhancement mechanisms. Low-temperature electrochemical reconstruction was used to prepare silver-based catalysts, and the effects of metal ion chelating agents including ethylenediaminetetraacetic acid, citric acid, and sodium citrate were also investigated. Results showed that Ag-SC, namely the catalysts fabricated with sodium citrate as chelating agent, exhibited highly selective CO production, with faradaic efficiency of 93.23% at −0.85 V (versus reversible hydrogen electrode, RHE) and CO partial current density of −7.92 mA cm⁻². Electrochemical impedance analysis confirmed low electron transfer resistance of Ag-SC, with 14.54 Ω, indicating superior electron transfer capability, and high ECR activity. Ag-SC also demonstrated excellent hydrophobicity, suppressing the competitive hydrogen evolution reaction and enhancing CO selectivity. In situ electrochemical reconstruction thus offers a simple, low-cost method for preparing silver-based catalysts tailored for ECR, with practical implications for electrode fabrication and catalytic material design.

Graphical Abstract