Synthesis and characterization of proton conducting Sr(Ce1−xZrx)0.95Yb0.05O3−δ by the citrate method

The citrate method was used to synthesize Sr(Ce1−xZrx)0.95Yb0.05O3−δ (x = 0.1, 0.2, 0.3, 0.4) and to avoid the drawbacks of the conventional solid state reaction method. The products were characterized by thermal analysis (TG-DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron probe X-ray microanalyzer (EPMA). The results indicate that the citrate method is an advantageous route in producing Sr(Ce1−xZrx)0.95Yb0.05O3−δ materials. Sr(Ce0.9Zr0.1)0.95Yb0.05O3−δ powders are composed of nanoscaled crystallites with the average grain size in the range of 60-70 nm. Single phase is confirmed over the whole x range. In addition, chemical stability against CO2 and electrical conduction behavior of the sintered Sr(Ce1−xZrx)0.95Yb0.05O3−δ ceramics were investigated. The chemical stability of the ceramics against CO2 is certified to increase with the increase in zirconium content. Impedance spectroscopy was used to study the electrical conduction behavior of Sr(Ce0.9Zr0.1)0.95Yb0.05O3−δ ceramic.