Plasma electrolytic synthesis and characterization of pH-sensitive TiO2-ZrO2-ZrTiO4-CeOx films on titanium

• Published in: Journal of solid state electrochemistry Vol. 27; no. 1; pp. 85 - 101
• Main Authors: Vasilyeva, M. S., Lukiyanchuk, I. V., Yarovaya, T. P., Arefieva, O. D., Shchitovskaya, E. V.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 2023; Springer Nature B.V
• Subjects: Additives; Alkalinity; Analytical Chemistry; Anatase; Aqueous electrolytes; Cerium; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Coatings; Composite materials; Composition; Condensed Matter Physics; Corrosion resistance; Corrosive wear; Electrochemistry; Electrodes; Electrolytes; Energy Storage; Original Paper; Oxidation; Physical Chemistry; Seawater; Titanium; Titanium dioxide; Titanium dioxide-Zirconia; Titration; Wear resistance; Yttrium; Zirconium dioxide; Zirconium titanates; Analysis of technogenic and sea waters; ceramics; pH response; ZrO; and ZrTiO; Plasma electrolytic oxidation; Modification with Ce and Y
• ISSN: 1432-8488; 1433-0768
• DOI: 10.1007/s10008-022-05306-8

The Ti/TiO 2  + ZrO 2 , Ti/TiO 2  + CeO x , and Ti/TiO 2  + CeO x  + ZrO 2 composites, including Y-doped ones, have been fabricated by one-stage plasma electrolytic oxidation (PEO) of titanium in aqueous electrolytes based on Zr(SO 4 ) 2 and/or Ce 2 (SO 4 ) 3 with and without additives of Y(CH 3 COO) 2 at effective anodic current density of 0.05 A/cm 2 for 10 min. SEM, XRD, and EDX methods have been used for investigation of the composition of the coatings. The resulting PEO coatings contain crystalline TiO 2 in rutile and anatase modifications. PEO coatings formed in 0.1 M Zr(SO 4 ) 2 electrolyte additionally include TiZrO 4 and m -ZrO 2 . The introduction of yttrium acetate or cerium sulfate into this electrolyte leads to the formation of t -ZrO 2 instead of m -ZrO 2 in the composition of PEO coatings. The pH sensitivity of obtained composites depends on the composition and morphology of their surface. The Ti/TiO 2  + CeO x  + ZrO 2 composite revealed the highest electrode function slope equal to 51 ± 1 mV/pH and excellent performance for end-point indication potentiometric acid–base titration similar to the conventionally used glass electrode. The Ti/Ce + Zr electrodes have shown excellent performance for determining the alkalinity of both technogenic waters and seawater. These composites are promising for use as wear- and corrosion-resistant pH solid-state sensors for long-term monitoring of highly saline waters, including seawater.