Giant dielectric constant response of the composites in ternary system CuO-TiO{sub 2}-CaO

Journal Article · Thu Oct 15 00:00:00 EDT 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.08.006· OSTI ID:21372369

Veith, Michael ^[1]; Shuhua, Ren; Wittmar, Matthias; Bolz, Henning ^[1]

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1. INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbruecken (Germany)

The subsolidus phase relations of the ternary system CuO-TiO{sub 2}-CaO sintered at 950 deg. C in air have been determined by powder X-ray diffraction method. Only one ternary compound CaCu{sub 3}Ti{sub 4}O{sub 12} was found in this system. From room-temperature dielectric property mapping at 10 kHz, a giant dielectric constant (epsilon{sub r}>10{sup 4}) was observed for most of the ceramic composites in the CuO-rich region and in the region along the CaO-CuO binary line. The composites in the CaCu{sub 3}Ti{sub 4}O{sub 12}-rich region were found to give a comparable giant dielectric constant when sintered at 1050 deg. C. The particular microstructure of larger grains with predominant phase surrounded by smaller grains with the secondary phases was found in such composites with a high dielectric constant. The relations between structures and dielectric properties were investigated. An internal barrier layer capacitance effect is the most probable mechanism to explain this particular dielectric behavior. - Graphical Abstract: In the ternary system, CuO-TiO{sub 2}-CaO, a giant dielectric constant (epsilon{sub r}) above 10{sup 4} (red color) was observed in most of the composites sintered at only 950 deg. C in the CuO-rich region. Dashed lines show the phase boundaries.

• OSTI ID: 21372369
• Journal Information: Journal of Solid State Chemistry, Vol. 182, Issue 10; Other Information: DOI: 10.1016/j.jssc.2009.08.006; PII: S0022-4596(09)00381-8; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CALCIUM OXIDES
CERAMICS
COPPER OXIDES
DIELECTRIC MATERIALS
KHZ RANGE 01-100
MICROSTRUCTURE
PERMITTIVITY
TEMPERATURE RANGE 0273-0400 K
TEMPERATURE RANGE 1000-4000 K
TITANIUM OXIDES
X-RAY DIFFRACTION
ALKALINE EARTH METAL COMPOUNDS
CALCIUM COMPOUNDS
CHALCOGENIDES
COHERENT SCATTERING
COPPER COMPOUNDS
DIELECTRIC PROPERTIES
DIFFRACTION
ELECTRICAL PROPERTIES
FREQUENCY RANGE
KHZ RANGE
MATERIALS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SCATTERING
TEMPERATURE RANGE
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS