Willow Catkin-like\nCo<sub>4</sub>S<sub>3</sub>–WS<sub>2</sub> Nanostructured Electrocatalyst\nfor Efficient Overall Alkaline\nWater Splitting

Exploring catalysts with high catalytic activity, abundant\nreserves,\nand low cost is of great significance for the hydrogen evolution reaction\n(HER). Polyoxometalates (POMs) have attracted extensive attention\nin recent years due to their rich structure and unique electrocatalytic\nproperties. In this study, a nanostructured Co<sub>4</sub>S<sub>3</sub>–WS<sub>2</sub> electrocatalyst was synthesized through a\nhydrothermal reaction using thiourea and polyoxometalate (Co<sub>5</sub>W<sub>19</sub>) as precursors. The synergistic effect between the\nprepared bimetallic cobalt tungsten sulfide nanomaterial (Co<sub>4</sub>S<sub>3</sub>–WS<sub>2</sub>) promoted electron transfer and\nimproved electrocatalytic performance exhibited excellent electrocatalytic\nactivity with lower overpotentials for hydrogen evolution and oxygen\nevolution reactions (OER) at 10 mA cm<sup>–2</sup>, namely,\n133 mV and 297 mV, respectively, with Tafel slopes of 114 mV dec<sup>–1</sup> and 55 mV dec<sup>–1</sup>. Additionally,\nthe material demonstrated long-term stability during continuous electrocatalysis.\nThe in situ growth of the Co<sub>4</sub>S<sub>3</sub>–WS<sub>2</sub> nanomaterial on carbon cloth via hydrothermal synthesis using\nthe POM precursor provides guidance and inspiration for designing\nefficient HER electrocatalysts.