A mechanical-electrochemical theory of defects in ionic solids

Narasimhan Swaminathan, Qu Jianmin

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

2 Scopus citations

Abstract

In this paper we present a coupled thermodynamic formulation to predict stresses, in an ionic solid due to diffusion of charged defects in an electrochemical potential gradient. Chemical expansion is considered primarily by treating compositional strains as eigen strains. Two material properties are introduced a) A second order tensor that represents the eigen strains in the solid due to non-stoichiometry and b) A fourth order tensor that represents the variations in elastic properties due to non-stoichiometry. A general theory is first developed for a steady state, isothermal condition, while considering typical electrochemical reactions at the interface and the bulk of a typical oxide ion conductor by considering all the major defects that are known to operate. Two geometries typical of solid electrolytes (planar and tubular) are considered, involving diffusion of vacancies and electrons. The governing equations are solved for the resulting stresses due to chemically induced strains resulting from a deviation in the stoichiometric composition of the solid. The results show the influence of considering the coupled problem on the distribution of defects, electrostatic potential, and the current voltage characteristics.

Original languageEnglish
Title of host publicationAdvances in Solid Oxide Fuel Cells II - A Collection of Papers Presented at the 30th International Conference on Advanced Ceramics and Composites
Pages125-136
Number of pages12
Edition4
StatePublished - 2006
EventAdvances in Solid Oxide Fuel Cells II - 30th International Conference on Advanced Ceramics and Composites - Cocoa Beach, FL, United States
Duration: 22 Jan 200627 Jan 2006

Publication series

NameCeramic Engineering and Science Proceedings
Number4
Volume27
ISSN (Print)0196-6219

Conference

ConferenceAdvances in Solid Oxide Fuel Cells II - 30th International Conference on Advanced Ceramics and Composites
Country/TerritoryUnited States
CityCocoa Beach, FL
Period22/01/0627/01/06

Fingerprint

Dive into the research topics of 'A mechanical-electrochemical theory of defects in ionic solids'. Together they form a unique fingerprint.

Cite this