Unveiling Synergistic CuAuAg Nanoparticles on CuO for High‐Yield CO ₂ Electroreduction

ABSTRACT The massive production of carbon dioxide (CO ₂ ) poses a serious threat to life on the Earth. Electrochemical CO ₂ reduction offers a promising route to convert CO ₂ into valuable fuels and feedstock chemicals. Among available catalysts, copper (Cu), a heterogeneous catalyst, exhibits excellent catalytic efficiency in converting CO ₂ to oxygenates and hydrocarbon fuels. Herein, to the best of our knowledge, we report for the first time the facile synthesis of trimetallic CuAuAg nanoparticles decorated on CuO sheets (CuAuAg/CuO composite) via the pulsed laser irradiation in liquid method, further used as a catalyst for the electroreduction of CO ₂ to various products, such as syngas (CO and H ₂ ), methane (CH ₄ ), formate, ethene (C ₂ H ₄ ), and ethane (C ₂ H ₆ ). A Faradaic efficiency of 77.34% was achieved for CO production using CuAuAg/CuO at −1.0 V versus reversible hydrogen electrode (RHE). In situ analysis of CuAuAg/CuO composite unveiled the CO ₂ reduction pathways, further confirmed via density functional theory. Notably, the trimetallic CuAuAg/CuO catalyst delivered a high CO yield rate of 5.1 mmol h ⁻¹ cm ⁻² at −1.0 V versus RHE. This study proclaims excellent CO ₂ conversion efficiency for large‐scale biofuel production and potential fuel cell applications.