Local and overall ionic conductivity in nanocrystalline CaF2

被引：111

作者：

Puin, W

Rodewald, S

Ramlau, R

Heitjans, P

Maier, J

机构：

[1] Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany

[2] Univ Hannover, Inst Phys Chem & Elektrochem, D-30167 Hannover, Germany

来源：

SOLID STATE IONICS | 2000年 / 131卷 / 1-2期

关键词：

tonic conductivity; nanocrystalline; CaF2;

D O I：

10.1016/S0167-2738(00)00630-5

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Ionic conductivity data on nanocrystalline CaF2 is evaluated. The d.c. conductivity is distinctly larger than in coarse-grained materials. The impedance plot exhibits two regimes: a high- and a low-frequency semicircle, the diameters of which increase with increasing grain size. The high-frequency semicircle reflects both bulk transport plus transport along the boundaries while the low-frequency semicircle describes the blocking effect of the grain boundaries. Absolute values and activation energy of the conductivity suggest dominating transport along space charge layers. The increase of the low frequency semicircle is due to increased current constriction because of the appearance of large pores. (C) 2000 Elsevier Science B.V. All rights reserved.

引用

页码：159 / 164

页数：6

共 17 条

[1] STUDY OF SOLID ELECTROLYTE POLARIZATION BY A COMPLEX ADMITTANCE METHOD [J].