One-Step Exsolution Strategy for the Reconstruction of the RuO₂/La_0.9Fe_0.92Ru_0.08O₃ Composite for the Enhanced Oxygen...

The noble metal oxide RuO₂ is an efficient catalyst for the oxygen evolution reaction (OER), and its catalytic activity can be significantly improved by Ru exsolution and subsequent oxidation to RuO₂ nanoparticles on the perovskite surface. Conventional methods typically require sequential H₂/Ar reduction for Ru exsolution followed by oxidation, which complicates the process and introduces potential safety hazards. Herein, we propose introducing nanodiamond (ND) into La_0.9Fe_0.92Ru_0.08O₃ (LFR) gels for ambient calcination. ND facilitates Ru exsolution and oxidation to RuO₂, significantly simplifying RuO₂/LFR preparation. The ND-modified RuO₂/LFR exhibits high OER activity, achieving an overpotential of 275 mV at 10 mA cm^-2 and a Tafel slope of 48.16 mV decade^-1. This Tafel slope represents a 50% reduction compared to that of pure RuO₂. Furthermore, the catalyst retains 84% of its initial current density after 24 h. Our work provides insight into enhancing electrocatalytic activity by a one-step in situ exsolution of metal oxides.