Modified g-C₃N₄/NiO nanocomposites for enhanced electrocatalytic efficiency in hydrogen evolution under alkaline conditions

Developing economical and effective hydrogen evolution reaction (HER) electrocatalysts is a key requirement for achieving sustainable energy solutions. In this report, g-C₃N₄/NiO nanocomposites were synthesized via a molten salt-assisted thermal method followed by ultrasonic treatment to achieve uniform integration and optimized interfacial contact. The resulting nanocomposites were systematically characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and field-emission scanning electron microscopy (FESEM) to confirm their structural, compositional, and morphological features. Electrochemical performances were evaluated in alkaline solution, revealing that g-C₃N₄/NiO nanocomposites showed enhanced HER performance compared to NiO nanoparticles. Notably, the nanocomposites achieved a Tafel slope of ∼40 mV/dec and a lower onset potential of –1.30 V versus Ag/AgCl, highlighting their superior catalytic efficiency. The enhanced HER performance could be attributed to the synergistic interface engineering among g-C₃N₄ and NiO, increased surface area, and enhanced electronic conductivity. This work reveals that g-C₃N₄/NiO nanocomposites serve as effective, economical, and robust electro-catalysts for alkaline water-splitting reactions.