NiMoO4-CuO nanorod array as electrocatalysts for efficient electrochemical hydrogen evolution reactions

Abstract

• The synthesis of NiMoO 4 -CuO /CF nanorods arrays is simple. • NiMoO 4 -CuO/CF has good HER activity and good stability. • The surface of NiMoO 4 -CuO/CF electrode has superhydrophilic and superaerophobic. • The formation process of bubbles on the electrode surface can be observed by CCD. Hydrogen is considered to be an energy source with a high potential to replace traditional fuels. Herein, NiMoO 4 -CuO nanorod arrays are constructed on copper foam (CF) substrate. Synergistic effect between NiMoO 4 and CuO can improve the electron transfer rate. Meanwhile, the superhydrophilic and superaerophobic structure of NiMoO 4 -CuO/CF promotes the diffusion of electrolyte and ensures the rapid release of bubbles. Therefore, only an overpotential of 59 mV is required to achieve the current density of 50 mA·cm −2 . At the current density of 50 mA·cm −2 for 24 h, the catalytic performance of the electrode has no obvious change, demonstrating that NiMoO 4 -CuO/CF electrocatalyst has outstanding stability, which provides a new pathway to synthesizing highly efficient HER electrocatalysts.