A dual layer Ni/Ni-YSZ hollow fibre for micro-tubular SOFC anode support with a current collector

A co-extrusion technique was employed to fabricate a dual layer NiO/NiO-YSZ hollow fibre precursor which was then co-sintered at 1400 °C and reduced at 700 °C to form, respectively, a meshed porous inner Ni current collector and outer Ni-YSZ anode layers for SOFC applications. Achieved morphology consisted of short finger-like voids originating from the inner bore of the hollow fibre, and a sponge-like structure filling most of the Ni-YSZ anode layer, which is considered to be suitable macrostructure for anode SOFC system. The electrical conductivity of the meshed porous inner Ni layer was measured to be 77.5 × 10⁵ S m^{- 1}. This result is significantly higher than previous reported results on single layer Ni-YSZ hollow fibres, which besides performing a catalyst function for the oxidation reaction also act as a current collector. These results highlight the advantages of this dual-layer hollow fibre design especially in developing a new and highly efficient way in current collection for micro-tubular SOFC.