High-active nanoplates of nitrogen-doped carbon@Mo2C as efficient catalysts in water splitting

Carbon doped metallic compounds have attracted a great deal of interest due to their new synergistic properties and enhanced catalytic performance from the doped-element induced defects. In this paper, polyaniline (PANI) is used as the carbon source to dope molybdenum carbide , which is annealed at 1000 °C to be nitrogen-doped carbon coupled with Mo 2 C (NC@Mo 2 C). Through the XRD , SEM and TEM methods the prepared NC@Mo 2 C composite is thoroughly characterized. The NC@Mo 2 C composite illustrates two-dimensional nanoplate morphology, and shows low overpotential in hydrogen evolution reaction (HER, 0.04 V) and oxygen evolution reaction (OER, 0.13 V) in 1 M KOH solution. Tafel slopes of NC@Mo 2 C for HER and OER are 100 mV decade −1 and 99 mV decade −1 , respectively, rather lower than pure Mo 2 C (HER: 130 mV decade −1 and OER: 126 mV decade −1 ). The Raman and XPS results show that it is the structural defects of Mo 2 C derived from NC doping that activate the reaction. Meanwhile, the NC doping and resulted defects enhance the conductivity of Mo 2 C, as well as endow NC@Mo 2 C nanoplates high electrochemical active surface area, facilitating the ion transfer, water absorption and gas desorption. The results of our work open up a new chance to design efficient non-noble metal-based catalysts for water electrolysis.