The use of hydrothermal procedures to synthesize NASICON and some comments on the stoichiometry of NASICON phases Academic Article uri icon


  • NASICON was prepared by a two step process. In the first step zirconium phosphate an Na4SiO4 are treated hydrothermally at 300°C. This produced a hydrated phase with approximate composition Na4Zr2Si2.25P1.8O15·H2O which could be indexed on the basis of an orthorhombic cell with a=8.743(1), b=10.317(4), c=7.317(1) A ̊. Upon heating this orthorhombic phase to 1100°C, P2O5 splits out to yield monoclinic NASICON of composition Na3.3Zr1.65Si1.9P1.1O11.5. This formula reflects both a deficiency of ZrO2 and Zr4+, compensated by Na+ for charge balance, over that required by Na1+xZrx2SixP3-xO12. It is proposed that both a NASICON series of the latter type and the defect type described in this paper exist, with the stoichiometric one being unstable and regarding to the defect structure upon heating. © 1983.

author list (cited authors)

  • Clearfield, A., Subramanian, M. A., Wang, W., & Jerus, P.

citation count

  • 29

publication date

  • December 1983