Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9803513 | Journal of Alloys and Compounds | 2005 | 5 Pages |
Abstract
Na2Sr1.5Nb3âxRuxO10 (x = 0.5, 1.0, 1.5) series compounds with Ruddlesden-Popper (RP) structure were synthesized by solid state reaction. The compounds were characterized by X-ray diffraction, thermal gravimetric analysis and X-ray photoelectron spectroscopy. The RP phase forms at 1050 °C. The compounds decompose when exposed to the ambient air at room temperatures for a long time. The cryogenic electrical behavior of Na2Sr1.5Nb1.5Ru1.5O10 can be described by variable range hopping (VRH) model. The electronic conduction at temperatures below 52 K is via two-dimensional hopping mechanism and three-dimensional hopping above that temperature. The high temperature electrical behavior of all compounds accords well with Ï = Ï0 exp(Ea/kT) relation. Both the resistivity and activation energy decrease with increasing Ru content in the compounds. The Na+ ions in all specimens are immobilized and thus cannot be exchanged with other ions such as Li+, K+.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Zhongbing Wang, Zuyao Chen, Mingde Li, Liezhao Cao,