Particle size dependence of oxygen evolution reaction on nanocrystalline RuO2 and Ru0.8Co0.2O2−x
- Resource Type
- Article
- Authors
- Jirkovský, Jakub; Makarova, Marina; Krtil, Petr
- Source
- Electrochemistry Communications. Sep2006, Vol. 8 Issue 9, p1417-1422. 6p.
- Subject
- *OXIDE minerals
*CHARGE transfer
*COLLOIDS
*PHOTOSYNTHETIC oxygen evolution
- Language
- ISSN
- 1388-2481
Abstract: Nanocrystalline RuO2 and Ru0.8Co0.2O2−x were prepared by a sol-gel synthesis. Both electrode materials were phase pure with tetragonal structure of rutile type. Characteristic particle size estimated from XRD pattern ranged between 15 and 45nm in the case of RuO2 and 20 and 60nm in the case of Ru0.8Co0.2O2−x . Both electrode materials show acceptable stability in acid media and are active electrocatalysts for oxygen evolution. Despite similar structure and chemical composition the oxygen evolution on RuO2 is controlled by charge transfer processes; the oxygen evolution on Ru0.8Co0.2O2−x is controlled by chemical steps of the electrode process. The oxygen evolution is in both cases affected by the particle size. Increasing particle size suppresses oxygen evolution on RuO2, but enhances it on Ru0.8Co0.2O2−x anodes. The opposite trends in electrochemical behavior of RuO2 and Ru0.8Co0.2O2−x are attributed to a specific effect of cobalt, which substitutes the Ru in the structure of the surface. [Copyright &y& Elsevier]