We demonstrate a new chemical route for the shape-controlled synthesis of a hybrid material derived from N-doped carbon and Mo2C (Mo2C-N-C) for the electrochemical hydrogen evolution reaction (HER) in acidic and basic medium. The synthetic procedure involves the facile complexation of Mo-precursor with cationic polymer, poly(diallyldimethyammonim chloride) (PDDA) and the subsequent carburization at 800 0C under optimized condition. The hybrid material was characterized by analytical techniques including XRD, XPS, Raman, TEM, etc. Electron microscopic measurements evidence the growth of nanowire bundles with length of 2-3 µm. The electrocatalytic activity was evaluated by recording the polarization curves in 0.5 M H2SO4 and 1 M KOH. We could achieve the benchmark current density of 10 mA/cm2 in acidic and alkaline pH at an overpotential of 136 and 183 mV, respectively. The catalytic performance is comparable to the existing Mo2C-based catalysts.3 The catalytic activity was further evaluated by calculating the Tafel analysis. A Tafel slope of 56 and 61 mV/dec was observed in acidic and alkaline pH, respectively. The Tafel analysis suggests that the electroctalytic hydrogen evolution involves Volmer-Heyrovsky mechanism. The hybrid material is highly durable and it retains its initial activity even after 1000 cycles. The superior performance can be explained by considering the surface morpholgy of Mo2C as well as the synergistic effect between the carbide catalyst and N-doped carbon.
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