Possible oxygen reduction reactions for graphene edges from first principles

Ikeda, Takashi; Hou, Z.*; Chai, G.-L.*; Terakura, Kiyoyuki*

Journal of Physical Chemistry C, 118(31), p.17616 - 17625, 2014/08

https://doi.org/10.1021/jp5038365

N-doped carbon-based nanomaterials are attracting a great interest as promising Pt-free electrode catalysts for polymer electrolyte fuel cells (PEFCs). In this computational study, we demonstrate that N-doped graphene edges can exhibit enhanced catalytic activity toward oxygen reduction reactions by controlling their electron-donating and -withdrawing abilities, and basicity, resulting in higher selectivity of 4e reduction via inner and outer sphere electron transfer at edges in acidic conditions, respectively. Our simulations also show that 2e reduction occurs selectively in the presence of pyridinic N next to carbonyl O at zigzag edges. This study thus rationalizes the roles of doped N in graphenelike materials for oxygen reduction reactions.