Halogen-incorporated Sn catalysts for selective electrochemical CO₂ reduction to formate

• Main Authors: Wang, Tian, Chen, Jiadong, Ren, Xinyi, Zhang, Jincheng, Ding, Jie, Liu, Yuhang, Lim, Kang Hui, Wang, Junhu, Li, Xuning, Yang, Hongbin, Huang, Yanqiang, Kawi, Sibudjing, Liu, Bin
• Other Authors: School of Chemical and Biomedical Engineering
• Format: Article
• Language: English
• Published: 2023
• Subjects: Engineering::Chemical engineering; Electrochemistry; Formate
• Online Access: https://hdl.handle.net/10356/168860
• Institution: Nanyang Technological University

Electrochemically reducing CO2 to valuable fuels or feedstocks is recognized as a promising strategy to simultaneously tackle the crises of fossil fuel shortage and carbon emission. Sn-based catalysts have been widely studied for electrochemical CO2 reduction reaction (CO2 RR) to make formic acid/formate, which unfortunately still suffer from low activity, selectivity and stability. In this work, halogen (F, Cl, Br or I) was introduced into the Sn catalyst by a facile hydrolysis method. The presence of halogen was confirmed by a collection of ex situ and in situ characterizations, which rendered a more positive valence state of Sn in halogen-incorporated Sn catalyst as compared to unmodified Sn under cathodic potentials in CO2 RR and therefore tuned the adsorption strength of the key intermediate (*OCHO) toward formate formation. As a result, the halogen-incorporated Sn catalyst exhibited greatly enhanced catalytic performance in electrochemical CO2 RR to produce formate.