Effect of Decomposition on the Densification and Properties of NASICON Ceramic Electrolytes

摘要

Processing and characterization of NASICON ceramic electrolytes have been conducted using a number of different techniques. Sintering of these materials was accomplished at temperatures between 1100 exp 0 C and 1375 exp 0 C. Results of this work have shown that NASICON ceramics with compositions around x=2 (i.e., Na sub 3 Zr sub 2 Si sub 2 Po sub 12 ), are not monophase, possess poor mechanical strength and an anomalous thermal expansion behavior, and are subject to chemical instability in the presence of liquid sodium (at 300 exp 0 C). Using wet-chemical techniques, x-ray diffraction analysis, and SEM observations, it was found that NASICON apparently exhibits phase and chemical decomposition at densification temperatures. The products of this decomposition process can be correlated with the poor physical and corrosion-resistant properties. (ERA citation 07:047023)