Ionic conductivity and structural characterization of Na 1.5Nb 0.3Zr 1.5(PO 4) 3 with NASICON-type structure (original) (raw)

The NASICON-type Na1.5Nb0.3Zr1.5(PO4)3 was prepared by solid state reaction of Nb2O5 and the precursor γ-NaHZr(PO4)2 at 700 °C. The EPR spectra showed a signal with a g factor of 1.984 assigned to Nb (IV) species in octahedral oxygen environments. The X-ray powder diffraction pattern obtained with monochromatic radiation was indexed on the basis of a rhombohedral cell, the hexagonal parameters being aH = 8.8061(2) and . The Na+ ion conduction was measured by the complex impedance method (frequency range: 0.1–105 Hz; temperature range: 20–500 °C) on four pellets previously sintered at 450, 750, 900 and 1000 °C. The conductivity data are discussed in relation to the sintering temperature. An activation energy of 0.60 eV for the movement of Na+ ions in the NASICON framework has been found.