A Networked Catalytic Layer Derived from Composite Nanowires Integrated with Pt Core and Active Pt-Doped RuO₂ Shell...

The deployment of ruthenium-based catalysts in low-loading anodes of proton exchange membrane water electrolyzers is hindered by their insufficient stability and limited catalyst utilization. This work presents a novel core-shell nanowire electrocatalyst (PRO@Pt) consisting of a Pt nanowire core coated with a Pt-doped RuO₂ active shell. Characterization and theoretical calculations reveal that the incorporation of Pt dopants and the resulting lattice expansion elevate the electron density on Ru sites, weaken Ru-O covalency, and optimize intermediate adsorption, thereby enhancing the electrocatalytic activity and stability of RuO₂ for oxygen evolution reaction. In 0.5 M H₂SO₄, PRO@Pt-2/18 exhibits a low overpotential of 173 mV at 10 mA cm^-2. Moreover, the catalyst network constructed by the intertwined PRO@Pt nanowire bundles avoids electrical isolation and ensures efficient electron transport throughout the electrode, even at a low loading. The single cell with the low-loading reticular catalyst layer (0.11 mg cm^-2) conveys an extremely low voltage of 1.72 V at 3 A cm^-2 and an average degradation rate of only 5 μV h^-1 in the latter stage of 1450 h of operation. This study provides a new strategy for developing efficient and durable low-loading anodes for industrial water electrolysis.