Speaker
Ms
Theeranuch Nachaithong
(Materials Science and Nanotechnology Program, Faculty of Science, Khon Kaen University, Khon Kaen, THAILAND 40002)
Description
The influence of annealing in Ar on the dielectric properties of CaCu${}_3$Ti${}_4$O${}_{12}$/CaTiO${}_3$ (CCTO/CTO) composites prepared by a solid state reaction method was studied. The phase composition and the microstructure were characterized by X-ray diffraction and scanning electron microscope with energy dispersive X-ray spectrometry, respectively. High dielectric permittivity values (2300$-$3000) with low loss tangent (0.01$-$0.03) at 1 kHz and room temperature were achieved in the CCTO/CTO composites. The dielectric permittivity was nearly independent on frequency in the range of 100$-$100000 Hz. Interestingly, the dielectric permittivity of the CCTO/CTO composites was largely reduced by annealing the sample in Ar atmosphere; while the low-frequency loss tangent value was largely increased. These results indicated to the decrease in the total resistance of the internal interfaces, i.e., CCTO-CCTO and CCTO-CTO interfaces. The dielectric behavior of the CCTO/CTO composites can be well explained based on the Maxwell-Wagner polarization at the internal interfaces.
Author
Ms
Theeranuch Nachaithong
(Materials Science and Nanotechnology Program, Faculty of Science, Khon Kaen University, Khon Kaen, THAILAND 40002)
Co-author
Dr
Prasit Thongbai
(Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen, THAILAND 40002)
