Structure and properties of titanium-based coatings in the anode environment of solid oxide fuel cells

Keywords

fuel cell, titanium interconnects, coatings, heat-resistance, surface electrical conductivity, humid hydrogen.

Cite as

Podhurska V. Ya., Chepil R. V., Kuprin О. S., Prikhna Т. О., Shchur Ya., Andrushchak A. S., and Ostash O. P. Structure and properties of titanium-based coatings in the anode environment of solid oxide fuel cells. Physicochemical Mechanics of Materials. 2026. 62(2), 047-054.

https://doi.org/10.15407/pcmm2026.02.047

Abstract

The effect of long-term (1000 h) holding at 600°С in the anode environment (a mixture of hydrogen and 30 vol.% water vapor) of solid oxide fuel cells (SOFCs) on the structure and properties of coatings deposited by the vacuum arc deposition method on thin (0.5 mm) titanium plates, which are considered as an alternative to steel interconnects in lightweight intermediate-temperature SOFCs, was investigated. Targets made of a composite based on the MAX phase Ti₂AlC (variant 1) and the Ti-6.1Al-5.5Zr-2.3Sn-0.8Mn-0.6Si-0.4Mo- 0.3Nb alloy (variant 2) were used. It was found that the oxidation resistance (Δm/S) and electrical conductivity (σ) of oxidized surfaces of these coatings in the anode environment were significantly reduced compared to those established in the cathode environment (after holding 1000 h in air at 600°С): Δm/S = 6.9 versus 0.06 mg/cm² and σ = 9×10^–1 versus 1.2×10⁶ S/m for the coating of variant 1; Δm/S = 16.1 versus 0.87 mg/cm² and σ = 5×10^–3 versus 2.4×10⁵ S/m for the coating of variant 2. It was shown that the high surface electri­cal conductivity of both coatings in the oxidized state after holding in the cathode envi­ron­ment was provided by TiO₂ oxide with anatase structure, and their low electrical conducti­vity in the anode environment was provided by TiO₂ oxide with rutile structure.

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