Ceramic injection moulding (CIM) has advantages for a cost effective fabrication of large-scale, near-net-shape products. In this work, CIM is carried out to prepare porous anode-support for solid oxide fuel cells (SOFC) applications. The CIM process started with a preparation of feedstocks by mixing powder with binder. The feedstock is then injected into the mould of desired shapes. The mouldings were subsequently undergo the removal of the binder (debinding) and, finally, sintering. It is shown that porous nickel oxide-yttria stabilized zirconia (NiO-YSZ) anode-support for SOFC were successfully prepared by CIM technique. In addition, a water-soluble based binder system, consisted mainly of polyethylene glycol (PEG), has been used in this work. This is to avoid the use of organic solvents when wax-based binder was used. Therefore, it can promote more environmentally friendly process. The removal of binder was carried out using water debinding technique. The porous anode for SOFC was subjected to systematic characterisation. The effect of processing parameters, such as powder characteristics and powder/binder ratio has been investigated. Rate of binder removal was also studied. The porous anode specimens were characterised for their properties and microstructure. It was also found that the porosity of the specimens can be controlled by adjusting the sintering temperatures and holding times.

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Thin film electrolyte made of 8-mol% yttria stabilized zirconia (8YSZ) was fabricated on porous NiO-8YSZ anode substrates using electrophoretic deposition (EPD). The porous NiO-8YSZ anode substrates were prepared by powder injection molding technique. The electrolyte suspensions containing 8YSZ nanoparticles and polyethylene glycol (PEG) as a dispersant (1-19 wt%) were formed in ethanol. The maximum zeta potential value was obtained from the 8YSZ suspension with 5 wt% PEG considered as an optimal content of PEG dispersant. The electrophoretic deposition of 8YSZ film was performed on the porous anode substrate using a constant voltage of 30 V for 150 sec prior to co-sintering at different temperatures in order to obtain dense 8YSZ electrolyte film on the porous anode substrate. Co-sintering at 1250°C for 1 h resulted in a formation of a dense 8YSZ thin-film electrolyte with a thickness of 6.35 mm. An open circuit voltage at 800°C of a single cell having 8YSZ thin-film electrolyte on porous NiO-8YSZ anode substrate was 1.09 V, indicating a gas-tightness of 8YSZ thin-film electrolyte fabricated by using EPD.