Graphene-based materials still exhibit poor electrocatalytic activities for the hydrogen evolution reaction (HER) although they are considered to be the most promising electrocatalysts. We fabricated a graphene-analogous material displaying exceptional activity towards the HER under acidic conditions with an overpotential (57 mV at 10 mA cm-2 ) and Tafel slope (44.6 mV dec-1 ) superior to previously reported graphene-based materials, and even comparable to the state-of-the art Pt/C catalyst. X-ray absorption near-edge structure (XANES) and solid-state NMR studies reveal that the distinct feature of its structure is dual graphitic-N doping in a six-membered carbon ring. Density functional theory (DFT) calculations show that the unique doped structure is beneficial for the activation of C-H bonds and to make the carbon atom bonded to two graphitic N atoms an active site for the HER.
Keywords: carbon materials; dual graphitic-N doping; electrocatalysis; hydrogen evolution reaction.
© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.