Integrated design and construction of WP/W nanorod array electrodes toward efficient hydrogen evolution reaction

Hitherto, WP has been used as hydrogen evolution reaction (HER) catalyst. However, its activity and complexity of nanostructure synthesis greatly limit applications in hydrogen production. Therefore, in this work, the coral-like WP nanorod arrays propagated on W foils (C-WP/W) are synthesized through an in situ oxidation and phosphorization route. The obtained 3D C-WP/W catalysis system can directly work as hydrogen evolution reaction (HER) electrode, and exhibits excellent activity and stability in either acid or alkaline media. It only requires a small overpotential of 109 and 133 mV at 10 mA/cm², and 189 and 206 mV at 100 mA/cm² in 0.5 M H₂SO₄ and 1.0 M KOH, respectively, which is the best HER catalyst ever reported among pure tungsten phosphide materials. This study paves the way for integrations of 3D HER electrodes with low-cost, high performance and for efficient applications under complicated conditions.