Nanostructured Ti/TiO2-RuO2-La2O3 anodes prepared by sol-gel process and the effect of electrolyte composition on their stability

Ti/TiO2-RuO2-La2O3 anodes were prepared by sol-gel process. The main aim of this work was to study nanostructured TiO2-RuO2-La2O3 coatings and the effect of electrolyte composition on their stability. For this purpose, coatings with different molar ratios applied on titanium substrate. Then, the morphology and electrochemical properties of the anodes in 0.5 M NaCl and 1 M H2SO4 solutions were studied using field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, potentiostatic polarisation, cyclic voltammetry, and accelerated corrosion test (ACT). The results showed that the morphology of all the coatings was cracked-mud microstructure and cracks with a width of 50-500 nm produced in the coatings. It was also observed that corrosion resistance, stability, and electrocatalytic properties of the anodes improve with increased La2O3 content. Then, the optimum TiO2-RuO2-La2O3 composition is obtained with a molar ratio of 70:15:15. Besides, the lifetime and stability of the anodes in NaCl solution were higher than H2SO4, so that the reduction of active elements in the coating with a molar ratio of 70:15:15 after ACT was obtained about 64.7 and 77.4% of before ACT in NaCl and H2SO4, respectively.