Low-temperature fabrication of protonic ceramic fuel cells with BaZr0.8Y0.2O3-δ electrolytes coated by aerosol deposition method

Abstract

To overcome the difficulties of sintering yttrium (Y)-doped barium zirconate (BZY), an aerosol deposition (AD) method is suggested as an attractive alternative since it produces dense BZY films in commercially large areas with high deposition efficiency at low temperature. In this study, highly Y-doped BZY powder for use in AD method was synthesized successfully without use of sintering additives; the process involves a series of careful preparation processes including pre-doping of Y, high-energy milling, and calcination with an atmospheric powder which maintains controlled BaO vapour pressure. It is noted that Y-doping of BaZrO3 in starting powder is important in the AD method. The increased conductivity of BZY electrolyte film using this powder resulted in relatively small Ohmic resistance (similar to 0.5 Omega cm(2) at 700 degrees C) and good cell performance (similar to 180 mW cm(-2) at 700 degrees C). These are one of the best performance among the reported values of cells that employ BaZr0.8Y0.2O3-delta (or BZY20) as an electrolyte. The high performance is also remarkable although the firing temperature of this cell (1200 degrees C) is much lower than those (>= 1400 degrees C) shown in literature studies. The performance can be further improved with appropriate choice of cathode and anode materials. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.