Structural transformations, water incorporation and transport properties of tin-substituted barium indate

Publication date: Available online 7 March 2018 Source:Journal of Solid State Chemistry Author(s): Kacper Cichy, Wojciech Skubida, Konrad Świerczek Incorporation of water into tin-substituted BaIn1-xSnxO3-δ (x = 0.1-0.3) is shown to influence crystal structure at room temperature, structural transformations at high temperatures and ionic transport properties of the materials. Increasing tin content stabilizes oxygen vacancy-disordered perovskite-type phase, which together with large changes of the unit cell volume occurring during hydration and dehydration processes, result in a complex structural behavior, as documented by high-temperature X-ray diffraction and thermogravimetric studies. Impedance spectroscopy measurements at elevated temperatures (350–800°C) revealed very high proton conductivity in BaIn0.8Sn0.2O3-δ, exceeding 1.1·10−3 Scm−1 at 500°C, with high values of the transference number in wet air. At the same time, relaxation kinetics of the electrical conductivity showed a monotonous nature, which indicates negligible component of the electronic hole conductivity in the hydrated material. The oxides are extremely moisture-sensitive, which results in a significant mechanical stability problems, affecting possibility to prepare electrolyte membranes. Graphical abstract

Source: Journal of Solid State Chemistry - March 9, 2018 Category: Chemistry Source Type: research