Electrophoretic deposition studies of Ba(Zr-Ce-Y)O-3 ceramic coating

Abstract

Electrophoretic deposition (EPD) is now a well established colloidal processing technique which uses electrophoresis mechanism for the movement of suspended charged particles in a suspension in the presence of an electric field. In this work, electrophoretic deposition of BaZr0.4Ce0.4Y0.2O3-delta (BZCY) in ethanol medium was performed under different conditions on both conducting and non-conducting (porous anode) substrate without using any external additives in a suspension bath. Process parameters such as deposition time, voltage, and rate of deposition of suspended particles were studied under various conditions. Green coating deposited under different potential (30, 50, and 70V) was uniform and crack free, even at extended time of deposition. Surface roughnesses have also been evaluated to correlate it with deposition conditions. It is also found that the rate of deposition on conducting substrate was higher as compared to that on non-conducting substrate (anode). XRD studies of the calcined powder and coating exhibit an expected simple cubic perovskite structure. The deposition yield increases linearly with voltage for each deposition time for both conducting and non-conducting substrates. The coating on non-conducting porous anode heat treated at 1500 degrees C for 2 hours was dense and well adherent to the anode substrate. A film thickness of about 13 mu m was obtained at 70V. Such dense BZCY electrolyte coating on BZCY+NiO anode (Half cell) could be well utilized for fabrication of proton conducting SOFC single cell by applying suitable cathode layer on electrolyte film.