Electron transfer and hydrogen spillover Co-driven to enhance hydrogen evolution reaction over oxygen-deficient tungsten oxide-supported iridium clusters

The development of low-loading precious metal-based electrocatalysts for hydrogen evolution reaction (HER) remains a research priority and technical challenge, requiring the effective utilization of robust interfacial interactions and synergistic effects between metal clusters and corresponding supporting substrates. Herein, a highly active electrocatalyst for hydrogen evolution with iridium (Ir) clusters boosted on oxygen-deficient tungsten oxide (W₁₈O₄₉) support is proposed via a one-pot hydrothermal strategy. The 1.16 wt% Ir/W₁₈O₄₉ catalyst demonstrates a low overpotential of 33 mV at 10 mA cm⁻², along with superior Ir mass activity (13.9 A mg⁻¹) at − 50 mV versus reversible hydrogen electrode (vs. RHE) that surpasses Ir/C, commercial 20 wt% platinum on carbon (Pt/C), and most reported precious metal-based catalysts. Theoretical calculations reveal that the synergistic modulation of electron transfer from Ir clusters to the W₁₈O₄₉ support and the hydrogen spillover effect regulate the hydrogen adsorption and desorption, thus enhancing the HER performance.