Examination of the co-sintering process of thin 8YSZ films obtained by dip-coating on in-house produced NiO–YSZ

Preparation conditions for obtaining dense 8YSZ electrolyte films by dip-coating on NiO–YSZ anode electrode substrates for SOFC application were investigated with focus on the co-sintering process. The NiO–YSZ substrates were prepared from nanoparticles which were obtained by a single modified sol–gel process using sucrose and pectin as organic precursors. The microstructure and the morphology of the product powders were analyzed by X-ray diffraction and TEM. A thin film of 8YSZ was obtained by a single-step dip-coating process using phosphate ester (PE) as dispersant and polyvinyl butyral (PVB) as binder. The microstructure of the sintered films was analyzed with SEM. The effect of the sinterability of the anode substrate on the 8YSZ film quality was studied. Fully dense electrolyte films were obtained on anode substrates which held a linear shrinkage of ∼23%. The use of substrates with a linear shrinkage below 23%, resulted in a poorly densified 8YSZ microstructure.