International Journal of Hydrogen Energy, Vol.39, No.27, 15039-15045, 2014
One-step synthesized nano-composite cathode material of Pr0.83BaCo1.33Sc0.5O6-delta-0.17PrCoO(3) for intermediate-temperature solid oxide fuel cell
Pr0.83BaCo1.33Sc0.5O6-delta-0.17PrCoO(3) (PBCS-0.17PCO) nano-composite material has been synthesized by a combined EDTA-citrate complexing sol gel method, and characterized as cathode material of intermediate-temperature solid oxide fuel cell (IT-SOFC). Phase structure has been characterized by X-ray diffraction (XRD) measurement. The results indicate that the composite material is composed of two cubic perovskite phases with nano-scaled grain sizes. Thermal expansion coefficient (TEC) of the composite material was measured to be 18.4 x 10(-6)/degrees C at temperatures of 30-900 degrees C. Electrical conductivities were measured in air by DC four-electrode method, and the conductivity values increase monotonically with the higher temperatures from 100 degrees C up to 750 degrees C. Electrochemical performance of the PBCS-0.17PCO composite materials was studied by electrochemical impedance spectra (EIS) measurements using GDC-based symmetric cell. Low area specific resistance (ASR) values ranging from 0.127 Omega cm(2) at 600 degrees C, 0.069 Omega cm(2) at 650 degrees C, 0.039 Omega cm(2) at 700 degrees C to 0.026 Omega cm(2) at 750 degrees C were achieved for the composite cathode, demonstrating its promising application in IT-SOFCs. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Keywords:Composite materials;Phase structure;Thermal expansion behavior;Electrical conductivity;Electrochemical performance