MnMoO nanosheet array: an efficient electrocatalyst for hydrogen evolution reaction with enhanced activity over a wide pH range.

We report the preparation of MnMoO nanosheet array on nickel foam (MnMoO NSA/NF) as an excellent 3D hydrogen evolution reaction (HER) electrocatalyst with good catalytic performance applied under basic, acidic and neutral conditions. In 0.5 M HSO, this MnMoO NSA/NF electrode needs an overpotential of 89 mV to drive current densities of 10 mA cm, to achieve the same current density, it demands overpotentials of 105 mV in 1.0 M KOH, 161 mV in 1.0 M PBS (pH = 7), respectively. After continuous CV scanning for 1000 cycles under different pH conditions, it also demonstrates an excellent stability with ignorable activity decrease. Such preeminent HER performance may be derived from the synergistic effect between manganese (Mn) and molybdenum (Mo) atoms, exposure of more active sites on the nanosheets and effective electron transport along the nanosheets. This MnMoO NSA/NF electrocatalyst provides us a highly efficient material for water splitting devices for industrial hydrogen production.