Electrocatalytic activity of biochar-supported ZnCoNi nanocomposite for hydrogen production from water splitting

As the global need for clean and renewable energy becomes more pressing, hydrogen (H₂) has emerged as a leading energy carrier due to its high energy density and zero-carbon emissions upon use. Among the various hydrogen production methods, water electrolysis stands out as a green and sustainable approach. However, its widespread application is still hindered by high overpotentials, slow kinetics of the hydrogen evolution reaction (HER), and the reliance on costly noble metal-based catalysts. This study addresses these limitations by developing cost-effective and efficient electrocatalysts using biochar as a carbon-based support material for the electrodeposition of mono-, bi-, and tri-metallic nanostructures containing zinc (Zn), cobalt (Co) and nickel (Ni). These transition metals were selected due to their favorable electrochemical propertiesstrong redox activity, high electrical conductivity and low cost, which are critical for facilitating HER kinetics. As a result of the electrochemical studies, the Biochar/ZnCoNi nanocomposite exhibited the best electrocatalytic performance, excellent long-term stability, high electrochemically active surface area and high durability. These results demonstrate that the synergistic integration of multimetallic nanostructures with biochar significantly enhances HER performance. By combining low-cost transition metals with sustainable carbon supports, this work provides a promising and scalable strategy for improving hydrogen production efficiency through water electrolysis, contributing meaningfully to the development of clean energy technologies and advancing the current state of HER catalyst research.