Built-in Electric Field Promotes Interfacial Adsorption and Activation of CO<sub>2</sub> for C<sub>1</sub> Products over a Wide Potential Window
Xin Zhao, Qingguo Feng, Mengjie Liu, Yuchao Wang, Wei Liu, Danni Deng, Jiabi Jiang, Xinran Zheng, Longsheng Zhan, Jinxian Wang, Huanran Zheng, Yu Bai, Yingbi Chen, Xiang Xiong, Yongpeng Lei
Abstract
The unsatisfactory adsorption and activation of CO 2 suppress electrochemical reduction over a wide potential window. Herein, the built-in electric field (BIEF) at the CeO 2 /In 2 O 3 n–n heterostructure realizes the C 1 (CO and HCOO – ) selectivity over 90.0% in a broad range of potentials from −0.7 to −1.1 V with a maximum value of 98.7 ± 0.3% at −0.8 V. In addition, the C 1 current density (−1.1 V) of the CeO 2 /In 2 O 3 heterostructure with a BIEF is about 2.0- and 3.2-fold that of In 2 O 3 and a physically mixed sample, respectively. The experimental and theoretical calculation results indicate that the introduction of CeO 2 triggered the charge redistribution and formed the BIEF at the interfaces, which enhanced the interfacial adsorption and activation of CO 2 at low overpotentials. Furthermore, the promoting effect was also extended to CeO 2 /In 2 S 3 . This work gives a deep understanding of BIEF engineering for highly efficient CO 2 electroreduction over a wide potential window.