A Highly Amorphous Multimetallic (Co, Fe, Ni, and W) Efficient Electrocatalyst for Overall Water Splitting in Basic Media and Hydrogen Evolution in Acidic Media

The global impact of industrial growth has resulted in a rapid elevation in consumption of gas and electricity, while corporations continue to produce excess amounts of gas and oil, but these are still insufficient to meet the energy demands worldwide. Research on alternative green energy fuels has become more popular as a result of this circumstance. Due to its renewable and environmentally favorable qualities, electrochemical water splitting has been considered the perfect alternative to fossil fuels. Thus, logical development of an extremely stable, cheap, and effective bifunctional catalyst is essential for complete water splitting application on a large scale. In the present work, a simple, eco-friendly, and scalable coprecipitation method was used to synthesize a highly disordered amorphous electrocatalyst (A-FNC), which, upon calcination, crystallizes into three distinct phases, i.e., Fe₂WO₆, NiWO₄, and WO₃. Various characterization techniques like PXRD, FESEM, HR-TEM, XPS, etc. were used to get a better insight into the structure and morphology of the synthesized catalyst. Previous reports show that amorphous phases are highly rich in defects, which are very beneficial in improving catalytic activity. The synergistic effect between Fe, Ni, and Co is believed to be one of the prime reasons which led to its exemplary electrocatalytic activity for the HER at extreme pHs and the OER in basic media. A detailed measurement and elucidation of several electrochemical techniques have been used to get a better insight into the catalytic properties for all the synthesized samples like overpotential, Tafel slope, stability, etc. Finally, the obtained η₁₀ for the alkaline electrolyzer in a two-electrode cell was 1.59 V, which surpasses that of many reported similar kinds of catalysts to date. These findings indicate a viable pathway for water electrocatalysis by using cost-effective amorphous electrocatalysts that are abundant on Earth and can be used for future applications.