The structure, morphology and electrical conductivity for BaZr0.8Y0.2O3-delta (BZY20) and BZY20 with ZnO sintering aid are compared. Both materials have a very dense structure. The bulk and total conductivities for BZY20 with ZnO sintering aid are lower than those of BZY20 in the range 400 to 650 degrees C. Both materials are stable up to 650 degrees C in hydrogen containing 5000 ppm H2S. Dense anode-supported electrolyte thin films are prepared using spin coating. (C) 2010 Elsevier B.V. All rights reserved.