Premium
Complex Impedance Study of Fine and Coarse Grain TiO 2 Ceramics
Author(s) -
Chao Sheng,
Petrovsky Vladimir,
Dogan Fatih
Publication year - 2010
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2010.04008.x
Subject(s) - dielectric spectroscopy , materials science , grain boundary , grain size , ceramic , dielectric , relaxation (psychology) , mineralogy , space charge , titanium dioxide , titanium , analytical chemistry (journal) , electron , composite material , metallurgy , chemistry , microstructure , electrochemistry , electrode , optoelectronics , psychology , social psychology , physics , quantum mechanics , chromatography
Titanium dioxide (TiO 2 ) ceramics with various grain sizes were investigated by impedance spectroscopy techniques. Dielectric loss peak identified in coarse grain TiO 2 was attributed to space charge polarization occurring at the grain boundaries. Electric modulus representation of the impedance data showed two types of relaxation processes in coarse grain TiO 2 , whereas only one type was observed in fine grain TiO 2 . Long‐range migration of oxygen vacancies was found to be the dominant conduction mechanism for fine grain TiO 2 , while electron hopping between localized states was attributed to dielectric relaxation in coarse grain TiO 2 .