OATAO - Open Archive Toulouse Archive Ouverte Open Access Week

Grain Growth-Controlled Giant Permittivity in Soft Chemistry CaCu3Ti4O12 Ceramics

Marchin, Loïc and Guillemet-Fritsch, Sophie and Durand, Bernard and Levchenko, Andrey A. and Navrotsky, Alexandra and Lebey, Thierry Grain Growth-Controlled Giant Permittivity in Soft Chemistry CaCu3Ti4O12 Ceramics. (2007) Journal of the American Ceramic Society, 91 (2). 485-489. ISSN 0002-7820

(Document in English)

PDF (Author's version) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader

Official URL: http://dx.doi.org/10.1111/j.1551-2916.2007.02174.x


We report a dielectric constant of up to 5.4105 at room temperature and 1 kHz for CaCu3Ti4O12 (CCTO) ceramics, derived from multiphase powders (coprecipitation products), made by a ‘‘chimie douce’’ (coprecipitation) method, and then sintered in air. The sintered products are pure-phase CCTO ceramics. The high dielectric constant is achieved by tuning the size of grains and the thickness of grain boundaries. The grain growth is controlled by varying the concentration of excess CuO in the initial powder (calcined coprecipitation products) between 1 and 3.1 wt%. The dielectric constant of pure CCTO ceramics increases with the initial CuO concentration, reaching its maximum at 2.4 wt% of CuO. A further increase of excess CuO in powders results in a permittivity decrease, accompanied by the formation of CuO as a separate phase in the sintered products. The unusual grain growth behavior is attributed to a eutectic reaction between CuO and TiO2 present in the initial powder.

Item Type:Article
Additional Information:Thanks to Blackwell Publishing editor. The definitive version is available at www.blackwell-synergy.com The original PDF of the article can be found at Journal of the American Ceramic Society website : http://www.ceramics.org/publications/jacers.aspx
Audience (journal):International peer-reviewed journal
Uncontrolled Keywords:
Institution:Other partners > University of California - UC Davis (USA)
Université de Toulouse > Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Université de Toulouse > Université Toulouse III - Paul Sabatier - UT3 (FRANCE)
French research institutions > Centre National de la Recherche Scientifique - CNRS (FRANCE)
Laboratory name:
Deposited On:04 Jun 2009 14:41

Repository Staff Only: item control page