Modulation\nfor RuO₂/TiO₂ via\nSimple Synthesis to Enhance the Acidic Oxygen Evolution Reaction

Abstract

Green hydrogen production with water splitting devices,\nespecially\na proton exchange membrane water electrolyzer (PEMWE), has received\nextensive attention. However, the sluggish kinetics of the oxygen\nevolution reaction (OER) still hinders its large-scale commercial\napplication. Designing high-performance and low-cost electrocatalysts\nto drive the OER reaction remains a tough challenge. The active nanoparticles\nincorporating with metal oxide support is considered a promising strategy\nto improve durability and activity in acidic electrolytes. However,\nefficient synthesis methods without support premodification are rarely\ninvestigated. Herein, a simple but effective hydrothermal method accompanying\nthe gradient annealing temperature was used to synthesize commercial\nTiO₂ supported RuO₂. The representative RuO₂/TiO₂-T250 required a low overpotential of 239\nmV (@10 mA cm^–2) with a Tafel slope value of 41.49\nmV dec^–1 and stability of over 20 h, far exceeding\nthe performance of commercial RuO₂. T250 exhibited a crystalline\nbut hydrated microstructure, and the existing support-metal oxide\ninteraction redistributed the electrons around Ru and Ti, which both\ngave rise to the activity of the electrocatalyst as well as hindered\nthe Ru dissolution, thereby enhancing the OER performance. The synthesis\nstrategy creates an important platform for designing more robust electrocatalysts\nfor PEMWE application.