Dynamic chloride ion adsorption on single iridium atom boosts seawater oxidation catalysis

• Main Authors: Duan, Xinxuan, Sha, Qihao, Li, Pengsong, Li, Tianshui, Yang, Guotao, Liu, Wei, Yu, Ende, Zhou, Daojin, Fang, Jinjie, Chen, Wenxing, Chen, Yizhen, Zheng, Lirong, Liao, Jiangwen, Wang, Zeyu, Li, Yaping, Yang, Hongbin, Zhang, Guoxin, Zhuang, Zhongbin, Hung, Sung-Fu, Jing, Changfei, Luo, Jun, Bai, Lu, Dong, Juncai, Xiao, Hai, Liu, Wen, Kuang, Yun, Liu, Bin, Sun, Xiaoming
• Other Authors: School of Chemistry, Chemical Engineering and Biotechnology
• Format: Article
• Language: English
• Published: 2024
• Subjects: Engineering; Sea water; Catalysis
• Online Access: https://hdl.handle.net/10356/174910
• Institution: Nanyang Technological University

Seawater electrolysis offers a renewable, scalable, and economic means for green hydrogen production. However, anode corrosion by Cl- pose great challenges for its commercialization. Herein, different from conventional catalysts designed to repel Cl- adsorption, we develop an atomic Ir catalyst on cobalt iron layered double hydroxide (Ir/CoFe-LDH) to tailor Cl- adsorption and modulate the electronic structure of the Ir active center, thereby establishing a unique Ir-OH/Cl coordination for alkaline seawater electrolysis. Operando characterizations and theoretical calculations unveil the pivotal role of this coordination state to lower OER activation energy by a factor of 1.93. The Ir/CoFe-LDH exhibits a remarkable oxygen evolution reaction activity (202 mV overpotential and TOF = 7.46 O2 s-1) in 6 M NaOH+2.8 M NaCl, superior over Cl--free 6 M NaOH electrolyte (236 mV overpotential and TOF = 1.05 O2 s-1), with 100% catalytic selectivity and stability at high current densities (400-800 mA cm-2) for more than 1,000 h.