Effects of Ni doping on the sintering and electrical properties of BaZr0.8Y0.2O3-δ proton conducting electrolyte prepared by Flame Spray Synthesis

BaZr0.8Y0.2xNixO3-delta (x=0.01, 0.02) prepared by Flame Spray Synthesis (FSS) were investigated as electrolyte materials for proton conducting fuel cells applications. The as synthesized nanoprecursors, composed of a perovskite phase mixed with doped zirconia and barium nitrate, were sintered at 1400 degrees C and 1500 degrees C to form dense specimens. The microstructural and electrical properties of the Ni doped sintered samples were compared with those related to the BaZr0.8Y0.2O3-delta sample sintered at 1600 degrees C. Ni inclusion strongly enhanced densification and grain growth process, reducing the sintering temperature up to 200 degrees C. AC impedance spectroscopy performed in wet H-2/N-2 atmosphere revealed a negative effect of Ni on the proton conductivity. The proton conductivity of 3.8 mS/cm(2) at 450 degrees C for the BaZr0.8Y0.18Ni0.02O3-delta sample sintered at 1400 degrees C, associated with the relatively low sintering temperature required, makes of Ni doped BZY20 prepared by FSS a promising electrolyte material for PCFCs working in the intermediate temperature range. (C) 2015 Elsevier Ltd. All rights reserved.