ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract The dependence of phase formation, sintering behavior, and electrical characteristics of Sodium Superionic Conductor (NASICON) compounds on sintering temperature, time, and cooling process was investigated. In the von Alpen-type composition Na3.2Zr1.3Si2.2P0.8O10.5, ZrO2 second phase is in thermal equilibrium with crystalline NASICON and liquid phase above 1320°C, and when cooled through 1260–1320°C, the crystalline NASICON was formed by reaction between the ZrO2 second phase and the liquid phase. Maximum relative densities of 96 and 91% were obtained for compositions Na3Zr2Si2PO12 and Na3.2Zr1.3Si2.2P0.8O10.5, respectively. For these compositions, the maximum ionic conductivity and the minimum migration barrier height were 0.45 ohm−1 cm−1 and 0.07 eV, respectively. The migration barrier height of the high temperature form (space group: R3c) is about 30–40% of that of the low temperature form (space group: C2/c). Ionic conductivity increases with increasing sinterability, and a considerably large amount of glass phase in Na3.2Zr1.3Si2.2P0.8O10.5 ceramics significantly lowers ionic conductivity above the transition temperature.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1004784327302
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