Nano crystalline Sr6Sb4NbO18-Energy Material in Solid Oxide Fuel Cells

Abstract

Because of the technological applications, Niobium based ceramic is one of the most research interest. Thus, there is numerous research works in recent years on their application as electronic and optical devices. Sintered oxide ceramics, having the required shape, micro structured size can be used for different electronic applications. In this paper, nano crystalline Sr6Sb4NbO18 ceramic was prepared by combustion method. The sample was analysed by the X-ray diffraction, TEM, radio frequency and Impedance spectroscopic studies. The XRD pattern of as prepared Sr6Sb4NbO18 sample reveals, the material has rhombohedral perovskite structure. All the peaks were broad when compared with the bulk, which indicates the reduction in the crystallite size. This is due to the micro strain and nano size in the crystallites. The crystallite size has been calculated from the XRD data, using Scherrer formula and it was obtained as 21 nm. The surface morphology of as prepared sample was studied using TEM and the particle size was found to be 19 nm. The sample was sintered at 1050 °C, obtained the 98 % of theoretical density. An impedance spectroscopic study of the sample carried out with a temperature range of, 200 °C to 500 °C shows that the ions are the main source for the conduction. The reason for the conductivity of the material might be because of the grain and grain boundary effects which can be clearly seen in the impedance plot. The impedance study confirms that the material is a possible candidate to fabricate solid oxide fuel cell.