Synthesis and Conductivity Study of Solid Electrolytes Li1 + xAlxGe2–x(PO4)3 (x = 0–0.65)


Cite item

Full Text

Open Access Open Access
Restricted Access Access granted
Restricted Access Subscription Access

Abstract

A new liquid-phase method has been suggested for synthesis of solid electrolytes with lithium conductivity of composition Li1 + xAlxGe2–x(PO4)3 (x = 0, 0.1, 0.3, 0.5, 0.6, 0.65) with a NASICON structure. The method is based on the use of an alkaline solution of GeO2 and water-soluble Al(NO3)3 · 9H2O, LiNO3, and (NH4)2HPO4 salts. The synthesized materials have been characterized by X-ray powder diffraction and impedance spectroscopy. The formation of crystalline Li1 + xAlxGe2–x(PO4)3 products with a NASICON structure is observed at 750–1000°C depending on the degree of substitution of germanium by aluminum. The effect of final powder annealing temperature and ceramics sintering temperature on the phase composition, density, and conductivity of resulting materials has been studied. The material of composition Li1.6Al0.6Ge1.4(PO4)3 produced by sintering the synthesized powder at 900°C exhibits the highest conductivity (3.8 × 10–4 S/cm at a ceramics density of 86%) and the lowest conductivity activation energy (30.5 ± 0.4 kJ/mol in the temperature range 25–250°C).

About the authors

M. A. Moshareva

Kurnakov Institute of General and Inorganic Chemistry

Email: novikova@igic.ras.ru
Russian Federation, Moscow, 119991

S. A. Novikova

Kurnakov Institute of General and Inorganic Chemistry

Author for correspondence.
Email: novikova@igic.ras.ru
Russian Federation, Moscow, 119991

Supplementary files

Supplementary Files
Action
1. JATS XML

Copyright (c) 2018 Pleiades Publishing, Ltd.