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.