Catalytic Activity of Nanosized Ruthenium Oxide-Coated Titanium Anodes Prepared by Thermal Decomposition for Oxygen Evolution in Sulfuric Acid Solutions

• Published in: Electrocatalysis Vol. 11; no. 5; pp. 505 - 512
• Main Authors: Kawaguchi, Kenji, Kimura, Shuhei, Morimitsu, Masatsugu
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.09.2021; Springer Nature B.V
• Subjects: Anodes; Anodic coatings; Anodic polarization; Catalysis; Catalytic activity; Chemical evolution; Chemistry; Chemistry and Materials Science; Current density; Electrochemistry; Electrode polarization; Electron transfer; Energy Systems; Mass transfer; Original Research; Oxygen; Particle size; Physical Chemistry; Ruthenium oxide; Sulfuric acid; Surface area; Thermal decomposition; Titanium; Oxygen evolution; Sulfuric acid solution; nanoparticles; Thermal decomposition; RuO; based anode
• ISSN: 1868-2529; 1868-5994
• DOI: 10.1007/s12678-020-00610-1

The effects of the nanoscale particle size of RuO 2 in thermally prepared RuO 2 -coated Ti anodes on electrochemical kinetic parameters such as the active surface area and Tafel slope for oxygen evolution in sulfuric acid solutions were investigated. RuO 2 /Ti anodes with four different average sizes of RuO 2 particles—5.6 nm, 6.8 nm, 14.6 nm, and 21.2 nm—were prepared. The double-layer charge corresponding to the active surface area for oxygen evolution of the anodes was shown to increase with decreasing average RuO 2 particle size. The polarization curves of the anodes showed that the oxygen evolution current density at a certain potential increased with decreasing average RuO 2 particle size, meaning that oxygen evolution, especially in the high-current-density region, where it mainly depends on the mass transfer rate, accelerated with decreasing RuO 2 particle size. The Tafel slope obtained for the anodes was shown to decrease with decreasing average RuO 2 particle size, indicating that the change in particle size affected the electron transfer rate for oxygen evolution. The present study reveals that changes in the nanoscale size of RuO 2 affect not only the mass transfer process but also the electron transfer process for oxygen evolution in sulfuric acid solutions. Graphical abstract