Pd-doped Urchin-like MnO2-carbon Sphere Three-dimensional (3D) Material for Oxygen Evolution Reaction

Carbon spheres (CSs) with an average diameter of around 500 similar to 700 nm are prepared by a extended Stober method. Urchin-like MnO2 nanorods were deposited on the carbon spheres by hydrothermal method and the thickness of alpha-MnO2 shell is about 700 similar to 800 nm. Pd particles with a diameter of around 8 similar to 15 nm are dispersed on the surface of vertically aligned alpha-MnO2 rods which have a diameter of 40 similar to 50 nm. Three-dimensional (3D) Pd-MnO2/CS shows better activity and stability than Pd/CS and MnO2/CS for anodic oxygen evolution reaction (OER) in water electrolysis, which shows that Pd-doped urchin-like CS-MnO2 core-shell structure material would be a superiority catalyst for the OER. The onset potential shifts negatively and current density improves on the Pd-MnO2/CS for the OER, showing a synergistic effect between Pd and MnO2. (C) 2016 Elsevier Ltd. All rights reserved.