Interstitial Sn-doping promotes electrocatalytic CO2-to-formate conversion on bismuth

• Published in: Science China materials Vol. 66; no. 9; pp. 3539 - 3546
• Main Authors: Xu, Xin, Wei, Yang, Mi, Linhua, Pan, Guodong, He, Yajun, Cai, Siting, Zheng, Chaoyang, Jiang, Yaming, Chen, Bin, Li, Liuyi, Zhong, Shenghong, Huang, Jianfeng, Hu, Wenbin, Yu, Yan
• Format: Journal Article
• Language: English
• Published: Beijing Science China Press 01.09.2023; Springer Nature B.V
• Subjects: Bismuth; Carbon dioxide; Catalytic activity; Catalytic converters; Chemistry and Materials Science; Chemistry/Food Science; Conversion; Density functional theory; Electrocatalysts; Electron transfer; Greenhouse effect; Materials Science; Nanowires; Stability; Tin; formate; interstitial doping; CO; reduction; electrocatalysis; bismuth
• ISSN: 2095-8226; 2199-4501
• DOI: 10.1007/s40843-023-2495-7

Electrochemical CO 2 reduction (CO 2 RR) is a promising technology to mitigate the greenhouse effect and convert CO 2 to value-added chemicals. Yet, achieving high catalytic activity, selectivity, and stability for target products is still a big challenge. Herein, interstitially Sn-doped Bi (Sn x -Bi, x is the atomic ratio of Sn to Bi, x = 1/2, 1/16, 1/24 or 1/40) nanowire bundles (NBs) are prepared by reducing Sn-doped Bi 2 S 3 . Notably, Sn 1/24 -Bi NBs exhibit ultrahigh formate selectivity over a broad potential window of 1400 mV (Faradaic efficiency over 90% from −0.5 to −1.9 V vs. reversible hydrogen electrode (RHE)) with an industry-compatible current density of −319 mA cm −2 at −1.9 V vs. RHE. Moreover, superior long-term stability for more than 84 h at ∼−200 mA cm −2 is realized. Experimental results and density functional theory (DFT) calculations reveal that interstitially doped Sn optimizes the adsorption affinity of *OCHO intermediate and reduces the electron transfer energy barrier of bismuth catalyst, resulting in the remarkable CO 2 RR performance. This study provides valuable inspiration for the design of doped electrocatalysts with enhanced catalytic activity, selectivity, and durability for electrochemical CO 2 -to-formate conversion.