• 文献标题:   Origin of the Electrocatalytic Oxygen Reduction Activity of Graphene-Based Catalysts: A Roadnnap to Achieve the Best Performance
  • 文献类型:   Article
  • 作  者:   JIAO Y, ZHENG Y, JARONIEC M, QIAO SZ
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
  • ISSN:   0002-7863 EI 1520-5126
  • 通讯作者地址:   Univ Adelaide
  • 被引频次:   500
  • DOI:   10.1021/ja500432h
  • 出版年:   2014

▎ 摘  要

The mutually corroborated electrochemical measurements and density functional theory (DFT) calculations were used to uncover the origin of electrocatalytic activity of graphene-based electrocatalysts for oxygen reduction reaction (ORR). A series of graphenes doped with nonmetal elements was designed and synthesized, and their ORR performance was evaluated in terms of four electrochemical descriptors: exchange current density, on-set potential, reaction pathway selectivity and kinetic current density. It is shown that these descriptors are in good agreement with DFT calculations, allowing derivation of a volcano plot between the ORR activity and the adsorption free energy of intermediates on metal-free materials, similarly as in the case of metallic catalysts. The molecular orbital concept was used to justify this volcano plot, and to theoretically predict the ORR performance of an ideal graphene-based catalyst, the ORR activity of which is comparable to the state-of-the-art Pt catalyst. Moreover, this study may stimulate the development of metal-free electrocatalysts for other key energy conversion processes including hydrogen evolution and oxygen evolution reactions and largely expand the spectrum of catalysts for energy-related electrocatalysis reactions.