Synthesis and characterisation of BaCeO3-based proton conductors obtained from freeze-dried precursors

A freeze-drying precursor method was used to obtain submicrometric powders of BaCeO3 and BaCe0.9Y0.1O3−δ proton conductors at temperatures as low as 800 °C. The phase formation and evolution with the temperature was studied by X-ray diffraction (XRD) and thermal analysis (TG-DTA). The microstructure of both powders and sintered pellets was examined by scanning electron microscopy (SEM). Dense ceramic materials were obtained at 1400 °C and the different contributions to the overall conductivity, bulk and grain boundary, were studied using impedance spectroscopy under different atmospheres.