Ni-enhanced molybdenum carbide loaded N-doped graphitized carbon as bifunctional electrocatalyst for overall water splitting

The development of bifunctional electrocatalyst for overall water splitting to obtain hydrogen fuel is a research hotspot at present due to the sustainability and non-pollution of hydrogen energy. Herein, Ni nanoparticles and Mo2C nanoparticles supported on N-doped graphitized carbon (NC) is successfully proposed via an one-step pyrolysis method by employing fish scales derivant as carbon source. The synergistic effects among Ni, Mo2C and NC can increase the active sites, reduce the electrochemical reaction energy barrier, and facilitate the electron transfer. As a result, the proposed optimal catalyst displays higher intrinsic activity (bearing an overpotential of 310 mV at the current density of 10 mA cm−2) toward the oxygen evolution reaction than a benchmark RuO2 electrocatalyst in alkaline electrolyte. Besides, the catalytic performance of hydrogen evolution reaction (bearing an overpotential of 101 mV at the current density of 10 mA cm−2) is close to that of commercial Pt/C in alkaline electrolyte. Furthermore, the proposed catalyst can maintain 24 h with stable property, which is very promising for industrial applications. This method of preparing Ni-Mo2C/NC composite electrocatalyst may provide a new route for transforming low-value biomass fish scales into high-value energy conversion materials.