Ag<sup>+</sup>‐Doped InSe Nanosheets for Membrane Electrode Assembly Electrolyzer toward Large‐Current Electroreduction of CO<sub>2</sub>to Ethanol
Xiangyu Wang, Zhiwei Jiang, Peng Wang, Zheng Chen, Tian Sheng, Zhengcui Wu, Yujie Xiong
Abstract
Abstract It is an appealing approach to CO 2 utilization through CO 2 electroreduction (CO 2 ER) to ethanol at high current density; however, the commonly used Cu‐based catalysts cannot sustain large current during CO 2 ER despite their capability for ethanol production. Herein, we report that Ag + ‐doped InSe nanosheets with Se vacancies can address this grand challenge in a membrane electrode assembly (MEA) electrolyzer. As revealed by our experimental characterization and theoretical calculation, the Ag + doping, which can tailor the electronic structure of InSe while diversifying catalytically active sites, enables the formation of key reaction intermediates and their sequential evolution into ethanol. More importantly, such a material can well work for large‐current conditions in MEA electrolyzers with In 2+ species stabilized via electron transfer from Ag to Se. Remarkably, in an MEA electrolyzer by coupling cathodic CO 2 ER with anodic oxygen evolution reaction (OER), the optimal catalyst exhibits an ethanol Faradaic efficiency of 68.7 % and a partial current density of 186.6 mA cm −2 on the cathode with a full‐cell ethanol energy efficiency of 26.1 % at 3.0 V. This work opens an avenue for large‐current production of ethanol from CO 2 with high selectivity and energy efficiency by rationally designing electrocatalysts.