Defective Indium/Indium Oxide Heterostructures for Highly Selective Carbon Dioxide Electrocatalysis
Wanfeng Yang, Yong Zhao, Sheng Chen, Wenhao Ren, Xianjue Chen, Chen Jia, Zhen Su, Yuan Wang, Chuan Zhao
Abstract
Electrochemical CO2 reduction to fuels and chemicals is a promising approach for CO2 utilization. Developing highly active, selective, and cost-effective electrocatalysts is the key to the large-scale application of this technology. Here, we report that defective indium/indium oxide heterostructures selectively catalyze CO2 electroreduction into C1 products in a broad potential range from −0.7 to −1.2 V vs RHE in aqueous media with the faradaic efficiency approaching 100%. This electrocatalyst enables an efficient CO2-to-formate conversion with excellent selectivity (up to 93%), activity (up to 50.8 mA cm–2), and durability (>25 h). The collaboration between metallic In and In oxide of the heterostructures attributes to the boosted electrochemical CO2 reduction: Metallic In mainly facilitates formate production, while In oxide suppresses the competing hydrogen evolution reaction. This study highlights the integration of different functional components/defects into heterostructures as an effective strategy for enhancing CO2 electrocatalysis.