On Lattice Distortion By Isovalent Cations In Silver Sulphate Solid Electrolyte

Department of Physics, Shri Shivaji Science College, Congress Nagar, Nagpur 440012, India

Adv. Mater. Lett., 2012, Current Issue, 3 (3), pp 204-212

DOI: 10.5185/amlett.2012.4332

Publication Date (Web): Jun 10, 2012

Copyright © IAAM-VBRI Press

E-mail: swanwane2000@yahoo.com

Abstract

Detailed impedance spectroscopic studies are carried out by incorporating various guest iso-valent cations within the solid solubility limit having different ionic radii in Ag₂SO₄. The solid solubility limits up to x = 3 mole% cation doped Ag₂SO₄ are set with XRD, SEM, IR and DSC techniques. A major dependence of conductivity on the ionic size of the doped iso-valent cations is observed. The ionic conductivity is found to increase with the incorporation of a guest cation that creates appropriate distortion factor in iso-valent cation doped Ag₂SO₄. The conductivity of Ag₂SO₄ is found to be dependent on the ionic size of the guest cation, particularly in the low-temperature modification of Ag₂SO₄ 4 (β-phase). These results could throw light on the fundamental conduction mechanism in Ag₂SO₄  and also on the criterion of selecting the impurity cation in the classical doping method. The optimized solid electrolytes can then be utilized for their technological applications in electrochemical devices such as SO_x sensors and thermal batteries.

Keywords

Lattice distortion, solid electrolytes, silver sulphate, fast ionic conductors.