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.

The NiCo₂O₄ nanorods were prepared by a hydrothermal method with nickel nitrate hexahydrate （Ni(NO₃)₂·6H₂O） as the nickel source,cobalt nitrate hexahydrate （Co(NO₃)₂·6H₂O） as the cobalt source,and urea as the precipitant.Then the above NiCo₂O₄ nanorods were immersed into the RuCl₃ solution to obtain the NiCo₂O₄/Ru composite catalyst by reduction.Testing technologies such as X?ray diffraction (XRD) and scanning electron microscopy (SEM) were adopted to characterize the phase structure and morphology of this composite catalyst, and its catalytic performance toward the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) was investigated by electrochemical methods such as linear scan voltammogram (LSV) and electrochemical impedance spectroscopy (EIS). Moreover, the NiCo₂O₄/Ru composite catalyst was used as the anode to assemble the Zn?air battery, whose open circuit voltage,charge and discharge performance,and cycle stability were evaluated by a LANHE test system. The results show that the NiCo₂O₄/Ru composite catalyst has high ORR/OER bifunctional catalytic activity with an OER overpotential of 420 mV at 10.0 mA/cm² and an ORR half?wave potential of 0.77 V.The assembled Zn?air battery also exhibits an open circuit voltage of 1.37 V, a maximum power density of 143 mW/cm²,as well as robust cycle stability for 50 hours.