Title: Effect of treatment temperature on microstructure and properties of nickel-zirconia anode materials for solid oxide fuel cells
Authors: Bogdan Vasyliv
Addresses: Department of Structural Fracture Mechanics of Materials, Karpenko Physico-Mechanical Institute, 5 Naukova str., Lviv 79060, Ukraine
Abstract: In this work, the structural, mechanical and electrical properties of YSZ-NiO anode ceramics before and after reduction in pure H2 and Ar-5 vol.%H2 mixture were studied. The NiO to Ni phase transformations that occur in the anode under reducing and reduction-oxidation (redox) cycling conditions and the impact on anode microstructure, strength and electrical conductivity have been examined. The results show that the redox treatment of the YSZ−NiO ceramic specimens influences on their properties controversially. At the treatment temperature 600° a structure providing improved physical and mechanical properties of the material is formed. However, at the treatment temperature 800° an anode structure with an array of microcracks is formed that significantly reduces the strength and electrical conductivity of the material. The results of this investigation show that reduction condition of YSZ-NiO is a powerful tool for influence on properties of the anode substrate.
Keywords: SOFC anode material; hydrogenous environment; high temperature; redox treatment; microstructure; strength; electrical conductivity.
International Journal of Process Systems Engineering, 2017 Vol.4 No.2/3, pp.162 - 168
Received: 29 Mar 2016
Accepted: 09 Sep 2016
Published online: 21 Jun 2017 *