Dielectric relaxation and giant dielectric constant of Nb-doped CaCu3Ti4O12ceramics under dc bias voltage

2009 ◽  
Vol 206 (3) ◽  
pp. 562-566 ◽  
Author(s):  
Peng Liu ◽  
Ying He ◽  
Jian-ping Zhou ◽  
Chun-hong Mu ◽  
Huai-wu Zhang
Keyword(s):  
Dielectric Constant ◽  
Dielectric Relaxation ◽  
Bias Voltage ◽  
Giant Dielectric ◽  
Dc Bias ◽  
Giant Dielectric Constant

scholarly journals Mean-Field Approach to Dielectric Relaxation in Giant Dielectric Constant Perovskite Ceramics

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Shanming Ke ◽  
Peng Lin ◽  
Haitao Huang ◽  
Huiqing Fan ◽  
Xierong Zeng
Keyword(s):  
Dielectric Constant ◽  
Dielectric Relaxation ◽  
Mean Field ◽  
Charge Carriers ◽  
Frequency Range ◽  
Polaron Model ◽  
Field Approach ◽  
Giant Dielectric ◽  
Perovskite Ceramics ◽  
Giant Dielectric Constant

The dielectric properties of CaCu3Ti4O3 (CCTO) and A2FeNbO6 (AFN, A = Ba, Sr, and Ca) giant dielectric constant ceramics were investigated in the frequency range from 1 Hz to 10 MHz. The relaxation properties can be perfectly described by a polaron model, indicating that the dielectric relaxation is intimately related to the hopping motion caused by localized charge carriers.

The Giant Dielectric Constant of Y2NiMnO6 Ceramics for DC Bias

2017 ◽  
Vol 866 ◽  
pp. 277-281
Author(s):  
Naphat Albutt ◽  
Suejit Pechprasarn ◽  
Pattaraporn Damkoengsuntorn ◽  
Thanapong Sareein
Keyword(s):  
Dielectric Constant ◽  
Dielectric Permittivity ◽  
Room Temperature ◽  
Frequency Range ◽  
Electronic Components ◽  
Giant Dielectric ◽  
High Dielectric Permittivity ◽  
Dc Bias ◽  
Giant Dielectric Constant ◽  
High Dielectric

In this work, the uses of giant dielectric constant of Y2NiMnO6 ceramics were investigated in the frequency range from 1 kHz to 3 MHz. The Y2NiMnO6 ceramics were sintered at 1400 °C for 6, 12, 18 and 24 hours, respectively. The dielectric properties of Y2NiMnO6 ceramics were examined in dc bias from 0 to 1.5 volt at room temperature. We found that all sintering times displayed high dielectric permittivity at frequencies below 105 Hz, above which the values decreased significantly, applied dc bias also reduced dielectric permittivity. The peak of dielectric loss decreased significantly at high dc bias due to decreased contribution of dc conductivity in grain ceramics. This research has characterised electrical properties of Y2NiMnO6 ceramics which maybe suitable for electronic components including batteries and capacitors.

scholarly journals Transport and Dielectric Properties of Mechanosynthesized La2/3Cu3Ti4O12 Ceramics

Crystals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 313
Author(s):  
Mohamad M. Ahmad ◽  
Hicham Mahfoz Kotb ◽  
Celin Joseph ◽  
Shalendra Kumar ◽  
Adil Alshoaibi
Keyword(s):  
Dielectric Constant ◽  
Sintering Temperature ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
Boundary Conductivity ◽  
X Ray ◽  
Giant Dielectric ◽  
Mechanochemical Milling ◽  
Giant Dielectric Constant ◽  
Lower Temperature

La2/3Cu3Ti4O12 (LCTO) powder has been synthesized by the mechanochemical milling technique. The pelletized powder was conventionally sintered for 10 h at a temperature range of 975–1025 °C, which is a lower temperature process compared to the standard solid-state reaction. X-ray diffraction analysis revealed a cubic phase for the current LCTO ceramics. The grain size of the sintered ceramics was found to increase from 1.5 ± 0.5 to 2.3 ± 0.5 μm with an increase in sintering temperature from 975 to 1025 °C. The impedance results show that the grain conductivity is more than three orders of magnitude larger than the grain boundary conductivity for LCTO ceramics. All the samples showed a giant dielectric constant (1.7 × 103–3.4 × 103) and dielectric loss (0.09–0.17) at 300 K and 10 kHz. The giant dielectric constant of the current samples was attributed to the effect of internal barrier layer capacitances due to their electrically inhomogeneous structure.

scholarly journals Colossal dielectric constant of NaNbO3 doped BaTiO3 ceramics

2016 ◽  
Vol 34 (2) ◽  
pp. 322-329 ◽  
Author(s):  
Wan Q. Cao ◽  
Ling F. Xu ◽  
Mukhlis M. Ismail ◽  
Li L. Huang
Keyword(s):  
Dielectric Constant ◽  
Dielectric Loss ◽  
Traditional Approach ◽  
Temperature Stability ◽  
Bound State ◽  
High Energy ◽  
Low Dielectric ◽  
Giant Dielectric ◽  
Giant Dielectric Constant ◽  
High Dielectric

AbstractBaTiO3 ceramics doped with 0.40 mol% NaNbO3 were prepared using a traditional approach by sintering at temperature of 1250 °C to 1290 °C. The prepared ceramics was characterized by very good dielectric properties, such as high dielectric constant (1.5 × 105), low dielectric loss (0.1), and good dielectric temperature stability in the −40 °C to 100 °C range for the sample sintered below 1270 °C. The dielectric characteristics obtained with XPS confirmed that Ti4+ ions remain in the state without any change. The huge increase in dielectric constant in NaNbO3 doped BaTiO3 samples occurs when large amount of Ba2+ ions are excited to a high energy bound state of Ba2+ − e or Ba+ to create electron hopping conduction. For samples with the content of NaNbO3 higher than 0.40 mol%, or sintering temperature higher than 1280 °C, compensation effect is dominated by cation vacancies with sharply decreasing dielectric constant and increased dielectric loss. The polaron effect is used to explain the relevant mechanism of giant dielectric constant appearing in the ferroelectric phase.

Giant dielectric constant and high-temperature dielectric relaxation properties in La-doped SrTiO3 ceramics

2020 ◽  
pp. 2150046
Author(s):  
Tianyang Liu ◽  
Xiaofei Wang ◽  
Congcong Li ◽  
Bowen Shen ◽  
Mingyan Yao ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
High Temperature ◽  
Temperature Region ◽  
Relaxation Processes ◽  
Doping Amount ◽  
Solid State Method ◽  
Giant Dielectric ◽  
Region I ◽  
Giant Dielectric Constant ◽  
Region Ii

[Formula: see text] (SLTO) ceramics ([Formula: see text] = 0.05, 0.10, 0.15) were prepared with giant dielectric constant by the traditional solid-state method at 1350[Formula: see text]C. The temperature dependence of the dielectric constant was obtained at the temperature ranging from 29[Formula: see text]C to 500[Formula: see text]C and the frequency ranging from 2 kHz to 2 MHz. Two sets of relaxation peaks appear in the low temperature (region I) and the high temperature (region II), respectively. For region I, we conclude that the relaxation behavior is related to the oxygen vacancy migration. For region II, the two relaxation processes are caused by grain boundary for high frequency and Sr or Ti defects at grain interior for low frequency. With the doping amount reaching 0.15, the relaxation peaks disappear and become a common phase transition because of the aggravation of lattice distortion. These possible physical mechanisms of two sets of relaxation peaks are briefly discussed.

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