@article{a6aa6ed78f754cf9ad90951c47aa9324,
title = "Manganese deception on graphene and implications in catalysis",
abstract = "Heteroatom-doped metal-free graphene has been widely studied as the catalyst for the oxygen reduction reaction (ORR). Depending on the preparation method and the dopants, the ORR activity varies ranging from a two-electron to a four-electron pathway. The different literature reports are difficult to correlate due to the large variances. However, due to the potential metal contamination, the origin of the ORR activity from “metal-free” graphene remains confusing and inconclusive. Here we decipher the ORR catalytic activities of diverse architectures on graphene derived from reduced graphene oxide. High angle annular dark field scanning transmission electron microscopy, X-ray absorption near edge structure, extended X-ray absorption fine structure, and trace elemental analysis methods are employed. The mechanistic origin of ORR activity is associated with the trace manganese content and reaches its highest performance at an onset potential of 0.94 V when manganese exists as a mononuclear-centered structure within defective graphene. This study exposes the deceptive role of trace metal in formerly thought to be metal-free graphene materials. It also provides insight into the design of better-performing catalyst for ORR by underscoring the coordination chemistry possible for future single-atom catalyst materials.",
keywords = "Heteroatom-doped graphene, Metal-free catalyst, Metal-free graphene, Oxygen reduction reaction",
author = "Ruquan Ye and Juncai Dong and Luqing Wang and Rub{\'e}n Mendoza-Cruz and Yilun Li and An, {Peng Fei} and Yacam{\'a}n, {Miguel Jos{\'e}} and Yakobson, {Boris I.} and Dongliang Chen and Tour, {James M.}",
note = "Funding Information: The Air Force Office of Scientific Research ( FA9550-14-1-0111 ) funded the work in the laboratory of J. M. T. The work by L. W. and B. I. Y. (computational modeling) was supported by the Office of Naval Research grant N00014-15-1-2372 . L.W. also acknowledges The Ken Kennedy Institutefor Information Technology 2016/17 Shell Graduate Fellowship. The work at UTSA was supported by the National Center for Research Resources ( 5 G12RR013646-12 ), NSF-PREM ( DMR 0934218 ) and the Welch Foundation through Grant No. AX-1615 to the International Center for Nanotechnology and Advanced Materials (ICNAM). J. D., P. A. and D. C. acknowledge support from the National Natural Science Foundation of China (Grant No. 11605225 ), the Youth Innovation Promotion Association, Chinese Academy of Science, and the Jialin Xie Foundation of Institute of High Energy Physics , Chinese Academy of Sciences . Funding Information: The Air Force Office of Scientific Research (FA9550-14-1-0111) funded the work in the laboratory of J. M. T. The work by L. W. and B. I. Y. (computational modeling) was supported by the Office of Naval Research grant N00014-15-1-2372. L.W. also acknowledges The Ken Kennedy Institutefor Information Technology 2016/17 Shell Graduate Fellowship. The work at UTSA was supported by the National Center for Research Resources (5 G12RR013646-12), NSF-PREM (DMR 0934218) and the Welch Foundation through Grant No. AX-1615 to the International Center for Nanotechnology and Advanced Materials (ICNAM). J. D., P. A. and D. C. acknowledge support from the National Natural Science Foundation of China (Grant No. 11605225), the Youth Innovation Promotion Association, Chinese Academy of Science, and the Jialin Xie Foundation of Institute of High Energy Physics, Chinese Academy of Sciences. Publisher Copyright: {\textcopyright} 2018 Elsevier Ltd",
year = "2018",
month = jun,
doi = "10.1016/j.carbon.2018.02.082",
language = "English (US)",
volume = "132",
pages = "623--631",
journal = "Carbon",
issn = "0008-6223",
publisher = "Elsevier Limited",
}