Anchoring magic NiCo2O4/NiO on Ni foam as an effective and binder-free electrocatalyst for boosting hydrogen evolution reaction

Electrocatalysts that can sustain water splitting without corrosion are required for large-scale water electrolysis applications. Thus, designing and constructing stable electrocatalysts is known as a crucial role in hydrogen evolution reactions (HER). Herein, NiCo2O4/NiO nanocubes on Ni foam (NF) as a stable electrocatalyst were fabricated successfully by using a facile hydrothermal method. Field Emission Scanning Electron Microscopy (FESEM) confirms the formation of distinct magic NiCo2O4/NiO/NF nanocubes with a size of 50-150 nm. The electrochemical tests indicated that the NiCo2O4/NiO nanocubes possess long stability of about 140 h and exceptional HER activity with a low overpotential of 38 mV at a current density of 10 mA.cm(-2) in a 1 M potassium hydroxide (KOH) and a Tafel slope of only 45 mV.dec(-1). The obtained results indicated that this level of HER catalytic performance is assigned to the rough surface and synergistic interactions between Ni and Co atoms in the nanocubes. It was also determined that the existence of NiO interface layer causes robust adhesion between NF and NiCo2O4 nanocubes. In addition, this discovery points to an advantageous future for the configuration and synthesis of highly effective, non-precious metal-based electrocatalysts for large-scale hydrogen production via water-splitting.