The potential use of a double B mixed-perovskite as a promising cathode material in intermediate temperature solid oxide fuel cells (IT-SOFCs) has been anticipated as a result of this work. A thorough investigation of some important parameters like thermal stability, thermal expansion, oxygen non-stoichiometry, electrical conductivity and diffusion characteristics of the PrNi0.6Fe0.4O3-delta ceramic sample have been investigated as functions of temperature (20-1000 degrees C) and oxygen partial pressure (0.6-21,000 Pa). According to the measurements, the composition was phase stable at pO(2) > 1 Pa up to 1000 degrees C and shows p-type semiconductivity with a low conductivity versus pO(2) dependence. The perovskite has been found to have comparable thermal expansion coefficients with those of commonly used solid electrolytes like CeO2 and ZrO2 based oxides. In case of the chemical diffusion experiments higher oxygen diffusion mobility observed during reduction processes in comparison with those during oxidation have been explained by the already known formation of neutral defect clusters. (c) 2011 Elsevier B.V. All rights reserved.