Coordination modulation of iridium single-atom catalyst maximizing water oxidation activity

• Published in: Nature communications Vol. 13; no. 1; pp. 24 - 10
• Main Authors: Lei, Zhanwu, Cai, Wenbin, Rao, Yifei, Wang, Kuan, Jiang, Yuyuan, Liu, Yang, Jin, Xu, Li, Jianming, Lv, Zhengxing, Jiao, Shuhong, Zhang, Wenhua, Yan, Pengfei, Zhang, Shuo, Cao, Ruiguo
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 10.01.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 119/118; 147/135; 147/137; 639/301/299/886; 639/638/77/884; 639/925/357/551; Arrays; Catalysts; Current density; Efficiency; Electrochemistry; Electrodes; Electrolytes; Energy; First principles; Humanities and Social Sciences; Hydrogen; Iridium; Iridium network; Iron sulfides; Laboratories; Life span; Morphology; multidisciplinary; Nanoparticles; Nanostructure; Nickel; Nickel iron; Oxidation; Precious metals; Scanning electron microscopy; Science; Science (multidisciplinary); Selectivity; Single atom catalysts; Stability; Substrates; Water splitting
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-27664-z

Single-atom catalysts (SACs) have attracted tremendous research interests in various energy-related fields because of their high activity, selectivity and 100% atom utilization. However, it is still a challenge to enhance the intrinsic and specific activity of SACs. Herein, we present an approach to fabricate a high surface distribution density of iridium (Ir) SAC on nickel-iron sulfide nanosheet arrays substrate (Ir 1 /NFS), which delivers a high water oxidation activity. The Ir 1 /NFS catalyst offers a low overpotential of ~170 mV at a current density of 10 mA cm −2 and a high turnover frequency of 9.85 s −1 at an overpotential of 300 mV in 1.0 M KOH solution. At the same time, the Ir 1 /NFS catalyst exhibits a high stability performance, reaching a lifespan up to 350 hours at a current density of 100 mA cm −2 . First-principles calculations reveal that the electronic structures of Ir atoms are significantly regulated by the sulfide substrate, endowing an energetically favorable reaction pathway. This work represents a promising strategy to fabricate high surface distribution density single-atom catalysts with high activity and durability for electrochemical water splitting. Single-atom catalysts represent a promising materials class for efficient catalytic transformations. Here, authors prepare a high surface distribution density of iridium atoms on nickel-iron sulfide nanosheet arrays to deliver high water oxidation activity and stability.