The precursor NiMoO4 nanorod arrays were prepared on nickel foam by a hydrothermal method using ammonium molydate tetrahydrate [(NH4)6Mo7O24·4H2O] as the Mo source and nickel nitrate hexahydrate [Ni(NO3)2·6H2O] as the Ni source, and subsequently were nitrogenized via a thermal treatment to obtain the NiMoN with rod?like array structure.The phase structure and surface morphology of the catalytic electrode material were characterized by X?ray diffraction (XRD) and scanning electron microscopy (SEM).Besides,the half?reaction oxygen evolution reaction (OER),hydrogen evolution reaction (HER),and overall water electrolysis performance of the material were evaluated by adopting various electrochemical characterizations,including linear scanning voltammetry (LSV),Tafel slope, and electrochemical impedance spectroscopy (EIS).The test results show that the NiMoN?9 catalytic electrode material has both high OER and HER activities.The OER overpotentials for this material to reach 100.00 mA/cm2 are only 293 mV and 340 mV respectively in alkaline fresh water and alkaline simulated seawater,while the corresponding HER overpotentials are 361 mV and 400 mV.In addition,the NiMoN?9 material also exhibits good activities in both water electrolysis and seawater electrolysis with the cell voltages of 2.016 V and 2.032 V respectively to obtain 100.00 mA/cm2 as well as robust stabilities over 55 h.