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The desire to achieve sustainable development goals inspired exploring green energy as a favorable alternative to hazardous fossil fuel‐based energy. Alkaline water electrolysis is a promising candidate for producing low‐cost pure green hydrogen; however, the efficiency of non‐precious transitional metal‐based catalysts is still behind noble electrocatalysts (like Pt and IrO2). To make hydrogen a next‐generation fuel, the replacement of high‐cost scarce noble metal is required. An attempt has been made to use a non‐precious transitional bimetallic combination of hafnium nickel diselenide/ reduced graphene oxide (HfNiSe2/rGO) for HER, OER, and overall water splitting. HfNiSe2/rGO demonstrated good electrocatalytic performance; for achieving 10 mA/cm2 of current density, the overpotential requirement is 162 mV for hydrogen evolution reaction (HER) and 320 mV for oxygen evolution reaction (OER) at 20 mA/cm2 of current density. Similarly, a low Tafel slope is required, 49 mV dec−1 for HER and 66 mV dec−1 for OER in 1 M KOH with high stability. HfNiSe2/rGO also showed highly stable activity for overall water splitting, requiring only 1.56 V to attain 10 mA/cm2 of current density. The result indicates HfNiSe2/rGO is a suitable electrocatalyst for green hydrogen generation because of its ease of production, economical, good activity, and stability towards water splitting.

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Electrochemical water splitting is a new approach toward sustainable energy sources. Developing nonprecious watersplitting electrocatalysts has attracted interest recently. On the other hand, nonprecious electrocatalysts excellent in oxygen and hydrogen evolution reactions are extremely limited and challenging. An efficient nanomaterial combination of hafnium cobalt sulfide/reduced graphene oxide (HfCoS/rGO) electrocatalyst was synthesized by hydrothermal synthesis. The proposed electrocatalyst was studied for electrocatalytic activity. The synthesized electrocatalyst showed excellent performance for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Low overpotentials of 164 and 210 mV for the HER and OER, respectively, are needed to achieve 10 mA/cm 2 . Similarly, smaller Tafel slopes of 49 and 46 mV/dec are required for the HER and OER, respectively, with long-term stability in alkaline media (1 M KOH). Utilizing a HfCoS/rGO bifunctional nonprecious electrocatalyst, a water-splitting electrolyzer can produce a current density of 10 mA/cm 2 using 1.60 V. Another outstanding result highlighted their enhanced catalytic activity, as evidenced by their long-term stability at various potentials. Developing efficient and economical H 2 production electrolyzers offers no difficulty in material synthesis, and the electrolyzer assembly can facilitate the development of a clean, renewable energy infrastructure.