THE ROLE OF SOL-GEL PROCEDURE CONDITIONS IN ELECTROCHEMICAL BEHAVIOR AND CORROSION STABILITY OF Ti/[RuO2-TiO2] ANODES

• Published in: Materials and manufacturing processes Vol. 20; no. 1; pp. 89 - 103
• Main Authors: Panić, V., Dekanski, A., Mišković-Stanković, V. B., Nikolić, B., Milonjić, S.
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 26-01-2005
• Subjects: Aging time; coating; Corrosion stability; Cyclic voltammetry; Electrochemical impedance spectroscopy; Forced hydrolysis; Oxide sols; Polarization measurements; Pore resistance; Pseudocapacitance; RuO; SEM; Sol-gel procedure; STM; TEM; TiO; XRD
• ISSN: 1042-6914; 1532-2475
• DOI: 10.1081/AMP-200041645

Using a sol-gel procedure, RuO
2
-TiO
2
active coatings were formed on a titanium support. The conditions of preparation of the RuO
2
and TiO
2
sols were investigated and the sols were characterized by transmission electron microscopy (TEM) and X-ray diffraction technique. Prepared anodes were investigated from the standpoint of morphology (scanning tunneling and electron microscopy) and electrochemical behavior (cyclic voltammetry, polarization measurements, and electrochemical impedance spectroscopy). The service life of the RuO
2
-TiO
2
active coatings was examined by an accelerated corrosion stability test in 0.5 ;mol dm
−3
NaCl solution. In order to resolve the role of TiO
2
in the deactivation mechanism of the active coating, additional TiO
2
layers were introduced in the support/coating interface or on the surface of the coating. The behavior of these anodes with the TiO
2
-enriched coating layer was compared with the behavior of anodes with regular RuO
2
-TiO
2
coatings. The results show that the loss of coating electrocatalytic activity is caused by dissolution of active Ru species and TiO
2
enrichment in the coating. It is also observed that the sol-gel preparation procedure favors the formation of the TiO
2
layer at the surface of the RuO
2
-TiO
2
coating.