Physical and electrical properties of combustion synthesized NASICON type Na3Cr2(PO4)3 crystallites: Effect of glycine molar ratios

Thermally stable Na3Cr2(PO4)3 nano-crystallites are synthesized through novel solution combustion technique using glycine fuel in three molar ratios. Effects of fuel molar ratio on structural and electrical properties are investigated. Reaction parameters like fuel molar ratio, flame temperature and number of moles of gases evolved, play a major role in deciding physical and electrical properties. Out of the synthesized samples, one which contains fuel in 1:1 molar ratio shows highest grain conductivity of 2.35 × 10−6 S cm−1. Improved conductivity is elucidated by least size and highest density of the crystallites, which in turn is decided by the flame temperature. Ac electrical properties are investigated using complex impedance spectroscopy. Activation energies for dc conduction and relaxation are determined and the results are reported.

► Synthesis of thermally stable NASICON type Na3Cr2(PO4)3 material for the first time by solution combustion technique.
► Glycine is used as fuel in different molar ratios.
► Fuel ratio influences physical and electrical properties.
► Nano-crystallites showed one order increase in conductivity compared to conventionally prepared material.
► Improved properties are correlated to the crystallite sizes and adiabatic flame temperature.
► Ac electrical relaxation studies are investigated using impedance spectroscopic technique.