Fabrication and electrical characterization of several YSZ tapes for SOFC applications

Y2O3 stabilized zirconia (YSZ) is frequently used as an electrolyte in solid oxide fuel cells (SOFC). Tape-casting is a readily available and easy-to-use option for obtaining thin, ceramic films with high relative density. In order to obtain fluid slips, rheological studies of aqueous suspensions of three different commercial YSZ powders dispersed with a polyacrylic acid-based dispersant agent have been performed. Their viscosity was optimized by controlling the dispersant concentration, pH and homogenization time using an ultrasound probe. An electrical study of the sintered tapes prepared under strict control of the rheology was done by electrochemical impedance spectroscopy. Their conductivity is compared to that obtained for non-optimized tapes, showing not big differences after the colloidal processing.