标题（英文）：Single atom iridium heterogeneous catalyst in oxygen reduction reaction

刊物名称及期号、页码：Angewandte Chemie

作者姓名（英文）：Meiling Xiaoa,f‡, Jianbing Zhuf‡, Gaoran Lif, Na Lib, Shuang Lib, Zachary Paul Canof, Lu Mac, Pei Xin Cuid, Pan Xuf, Gaopeng Jiangf, Huile Jina, Shun Wang^a*, Tianpin Wuc*, Jun Lue, Aiping Yuf, Dong Sub*, Zhongwei Chen

摘要（英文）：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 asdeveloped 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-1Ir, 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 IrSAC is attributed to the moderate adsorption energy of reaction intermediates on the mononuclear iridium ion coordinated with four nitrogen atom sites.

原文链接：

https://doi.org/10.1002/ange.201905241