Carburized In<sub>2</sub>O<sub>3</sub> Nanorods Endow CO<sub>2</sub> Electroreduction to Formate at 1 A cm<sup>–2</sup>
Wenhang Wang, Xiaoshan Wang, Zhengguang Ma, Yang Wang, Zhongxue Yang, Jiexin Zhu, Lei Lv, Hui Ning, Noritatsu Tsubaki, Mingbo Wu
Abstract
The double high index of current density and Faradaic efficiency in carbon dioxide electroreduction is a great challenge. Herein, we synthesized carburized indium oxide nanorods (In2O3-C) by pyrolysis of the metal–organic framework (MOF) precursor [MIL-68 (In)]. The electronic structure of In was regulated, and the localization of negative charges was increased on the surface of the In2O3-C catalyst, resulting in a high Faradaic efficiency of 97.2% at −1.0 V vs RHE and above 90% in a wide potential range of 500 mV. Furthermore, it reached a current density of −1.0 A·cm–2 in the flow cell for producing formate efficiently. The complete reaction path from CO2 to formate on In2O3-C was in situ investigated by attenuated total reflection surface-enhanced infrared adsorption spectroscopy and 2D/3D surface-enhanced Raman spectroscopy.