Ga-Based Ga@In4Ag9/Cu for CO2 Electroreduction to CO in a Three-Chamber Electrolyzer: With NaOH and Cl2 as Byproducts.

Abstract

Electroreduction of carbon dioxide (CO2RR) using renewable energy offers a sustainable approach for generating valuable chemicals. In this study, a three-chamber electrolyzer was utilized for the direct coproduction of CO, Cl2, and NaOH from CO2 and NaCl electrolysis, contributing to net CO2 consumption and supporting industries like phosgene synthesis. To improve the electrolyzer performance, a Ga-based metal composite catalyst (Ga@In4Ag9/Cu) was developed. This catalyst efficiently reduced CO2 to CO during long-term electrolysis, achieving a CO partial current density of 147.16 mA·cm-2 and a faradaic efficiency of 93.1% at -2.4 V (vs SHE). Density functional theory (DFT) calculations revealed that Ag atoms modulate the d-band center of Ga@In4Ag9/Cu, enhancing its interaction with the reaction intermediates. This work introduces a Ga-based porous catalyst for CO2 electrolysis in organic electrolytes, offering a promising system for the coproduction of CO, Cl2, and NaOH through a coupled reaction.