A Single‐Atom Iridium Heterogeneous Catalyst in Oxygen Reduction Reaction

Journal Article · 18 June 2019 · Angewandte Chemie (International Edition)

DOI: https://doi.org/10.1002/anie.201905241 · OSTI ID:1526780

Xiao, Meiling ^[1]; Zhu, Jianbing ^[2]; Li, Gaoran ^[2]; Li, Na ^[3]; Li, Shuang ^[3]; Cano, Zachary Paul ^[2]; Ma, Lu ^[4]; Cui, Peixin ^[5]; Xu, Pan ^[2]; Jiang, Gaopeng ^[2]; Jin, Huile ^[6]; Wang, Shun ^[6]; Wu, Tianpin ^[4]; Lu, Jun ^[7]; Yu, Aiping ^[2]; Su, Dong ^[3]; Chen, Zhongwei  ^[2]

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1. College of Chemistry and Materials Engineering, Institute of New Materials and Industrial Technologies Wenzhou University Wenzhou Zhejiang 325035 China, Department of Chemical Engineering University of Waterloo Waterloo Ontario Canada
2. Department of Chemical Engineering University of Waterloo Waterloo Ontario Canada
3. Centre for Functional Nanomaterials Brookhaven National Laboratory Upton NY USA
4. X-Ray Science Division Argonne National Laboratory Lemont IL 60439 USA
5. Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 P. R. China
6. College of Chemistry and Materials Engineering, Institute of New Materials and Industrial Technologies Wenzhou University Wenzhou Zhejiang 325035 China
7. Chemical Sciences and Engineering Division Argonne National Laboratory Lemont IL 60439 USA

Abstract Combining the advantages of homogeneous and heterogeneous catalysts, single‐atom catalysts (SACs) are bringing new opportunities to revolutionize ORR catalysis in terms of cost, activity and durability. However, the lack of high‐performance SACs as well as the fundamental understanding of their unique catalytic mechanisms call for serious advances in this field. Herein, for the first time, we develop an Ir‐N‐C single‐atom catalyst (Ir‐SAC) which mimics homogeneous iridium porphyrins for high‐efficiency ORR catalysis. In accordance with theoretical predictions, the as‐developed Ir‐SAC exhibits orders of magnitude higher ORR activity than iridium nanoparticles with a record‐high turnover frequency (TOF) of 24.3 e ⁻ site ⁻¹  s ⁻¹ at 0.85 V vs. RHE) and an impressive mass activity of 12.2 A mg ⁻¹ _Ir , which far outperforms the previously reported SACs and commercial Pt/C. Atomic structural characterizations and density functional theory calculations reveal that the high activity of Ir‐SAC is attributed to the moderate adsorption energy of reaction intermediates on the mononuclear iridium ion coordinated with four nitrogen atom sites.

• Sponsoring Organization: USDOE
• Grant/Contract Number: SC0012704; AC02-06CH11357
• OSTI ID: 1526780
• Journal Information: Angewandte Chemie (International Edition), Journal Name: Angewandte Chemie (International Edition) Vol. 58 Journal Issue: 28; ISSN 1433-7851
• Publisher: Wiley Blackwell (John Wiley & Sons)Copyright Statement
• Country of Publication: Germany
• Language: English