Earth-Abundant W₁₈O₄₉ Coupled with Minimal Pt for Enhanced Hydrogen Evolution under Dark and Visible Light Conditions

The development of cost-effective and efficient electrocatalysts for the hydrogen evolution reaction (HER) is critical to advancing green hydrogen production technologies. Here, we present a plasmonic tungsten oxide (W₁₈O₄₉) material integrated with ultralow platinum (Pt) loadings (0.4, 0.8, and 1.6 wt %) that delivers high HER performances under both dark and visible light conditions. The 0.4 wt % Pt-W₁₈O₄₉ catalyst exhibits remarkable mass activity, outperforming commercial Pt/C by factors of 15 and 30 under dark and 740 nm LED illumination, respectively. Density functional theory (DFT) calculations reveal that the synergy between Pt and plasmonically active W₁₈O₄₉ optimizes charge transfer and hydrogen adsorption, resulting in lowered energy barriers for HER kinetics. Furthermore, plasmonic excitation of W₁₈O₄₉ enhances catalytic activity by facilitating electron transfer. This work introduces a scalable, cost-effective strategy for combining earth-abundant plasmonic materials with minimal Pt usage, providing a pathway toward high-efficiency HER catalysts. These findings highlight the potential of plasmonic-catalyst integration in green hydrogen technologies.