Porous Ni/TiO2 substrates for planar solid oxide fuel cell applications

Anode substrates based on Ni/TiO2 cermets were fabricated for planar solid oxide fuel cells (SOFCs) with the aim of reducing the material costs and pr eventing thermoelastic bending of the currently used Ni/8YSZ-based cells. N i/TiO2 substrates were produced via sintering of NiO/NiTiO3 powder compacts and subsequent reduction. The sintering behavior in air and the resulting microstructure were studied in detail. Excellent electrical conductivity an d gas permeability was achieved before and after reduction due to coarse mi crostructure. The co-firing behavior of substrates coated with an anode lay er and an 8YSZ electrolyte membrane was analyzed with the aim of identifyin g those sintering schedules which give flat cells with a gastight electroly te. Thermoelastic bending of cells is negligible since the thermal expansio n coefficient is well adjusted to the 8YSZ electrolyte. (C) 2001 Kluwer Aca demic Publishers.