A highly efficient and stable biphasic nanocrystalline Ni–Mo–N catalyst for hydrogen evolution in both acidic and alkaline electrolytes

The hydrogen evolution reaction (HER) is of critical importance for sustainable hydrogen production from water electrolysis. In this work, we report a highly efficient and stable noble metal free HER catalyst, which is composed of homogeneously distributed metallic Ni and NiMo4N5 nanocrystals. The biphasic nanocrystalline Ni–Mo–N catalyst shows very low overpotential (53 mV in 0.5 M H2SO4 and 43 mV in 1 M KOH, at current density 20 mA/cm2) and good stability for HER in both acidic and alkaline electrolytes, which is a promising low cost alternative for platinum based HER catalysts.