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.

scholarly journals Colossal Permittivity and Multiple Effects in (Zn + Ta) co-doped TiO2 Ceramics

2020 ◽  
Author(s):  
Jiangtao Fan ◽  
TianTian Yang ◽  
Zhenzhu Cao
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Low Dielectric ◽  
Giant Dielectric ◽  
High Dielectric Permittivity ◽  
Colossal Permittivity ◽  
Giant Dielectric Constant ◽  
High Dielectric ◽  
Device Miniaturization ◽  
Co Doped

Abstract The search for giant dielectric constant materials is imperative because of their potential for important applications for the areas of device miniaturization and energy storage. In this work, we report a (Zn + Ta) co-doped TiO2 (ZTTO) ceramics that manifests high dielectric permittivity (>104) and low dielectric loss. This dielectric property shows a high stability in wide temperature range (25-200℃) and frequency range(20-106Hz). The crystalline structure, microstructure and dielectric properties of ZTTO ceramics were systematically investigated. XPS, Impedance spectroscopy and frequency dependent dielectric constant under DC bias results reveal that the colossal dielectric properties of (Zn2+1/3Ta5+2/3)xTi1-xO2 ceramics were mainly caused by electron-pinned defect-dipoles (EPDD) model, internal barrier layer capacitance (IBLC) effect and electrode effect. This work would provide a guidance to further researching the colossal permittivity CP materials.

High dielectric constant and low dielectric loss of Y/Mn co-doped BST@ZrO2/PVDF composite films for wearable capacitor applications

2020 ◽  
pp. 2151004
Author(s):  
Jingru Zhang ◽  
Ruoxin Xu ◽  
Xiao Han ◽  
Zhiang Zhang ◽  
Lili Zhao ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Dielectric Loss ◽  
Polyvinylidene Fluoride ◽  
High Dielectric Constant ◽  
Composite Films ◽  
Temperature Stability ◽  
Co Doping ◽  
Low Dielectric ◽  
High Dielectric ◽  
Co Doped

In order to develop infinite capacitive materials with high dielectric constant and low dielectric loss, influences of Y/Mn co-doping and ZrO2 coating on the dielectric properties of barium strontium tinanate/polyvinylidene fluoride (BST/PVDF) composite films were systematically investigated with fixing Y concentration as 0.3 at.% and varying Mn concentration from 1 at.% to 4 at.%. The experimental results show that the dielectric constant of BST@ZrO2/PVDF composite increases by 50% relative to BST/PVDF and the dielectric loss is evidently depressed. In comparison with BST@ZrO2/PVDF sample, furthermore, the dielectric constant of Y/Mn co-doped BST@ZrO2/PVDF samples increases by about 60% and the dielectric loss further reduces at 1 kHz. The promoted dielectric performances of composite originate from the space charge separation formed by Y/Mn co-doping and the limitation of electronic mobility by coated ZrO2. Y/Mn co-doped BST@ZrO2/PVDF composite film with 3% Mn has a dielectric constant of 37.9, a dielectric loss of 0.0117, superior dielectric temperature stability (3.1% from -5[Formula: see text]C to 45[Formula: see text]C at 1 kHz), and a discharged energy density of 5.67 J/cm3 at 600 kV/cm. The simultaneous optimization of dielectric constant and dielectric loss of BST/PVDF composite is realized in this experiment. The superior dielectric temperature stability suggests the application potential of Y/Mn co-doped BST@ZrO2/PVDF as wearable capacitors.

Composition-Microstructure-Property Relationships in BaTiO3 with Mg Addition

2015 ◽  
Vol 659 ◽  
pp. 58-63
Author(s):  
Oratai Jongprateep ◽  
Tunchanoke Khongnakhon ◽  
Jednupong Palomas
Keyword(s):  
Dielectric Constant ◽  
Dielectric Loss ◽  
Barium Titanate ◽  
High Efficiency ◽  
High Dielectric Constant ◽  
Dielectric Materials ◽  
High Energy ◽  
High Energy Density ◽  
Low Dielectric ◽  
High Dielectric

Rising worldwide demands for energy encourages development of high-efficiency energy storage and capacitor components. Main requirements for dielectric materials employed in fabrication of high energy density capacitors include high dielectric constant, high dielectric breakdown strength, and low dielectric loss. Owing to its high dielectric constant and low dielectric loss [1], barium titanate is among common capacitor materials. Tailoring of dielectric properties of barium titanate can be achieved through controlled chemical composition, microstructure, and crystal structure. Synthesis and processing techniques, as well as doping of barium titanate, can be key factors to control the composition and structure, which consequently contribute to enhancement of dielectric constant in the material.

Skin–core structured fluorinated MWCNTs: a nanofiller towards a broadband dielectric material with a high dielectric constant and low dielectric loss

2018 ◽  
Vol 6 (9) ◽  
pp. 2370-2378 ◽  
Author(s):  
Yang Liu ◽  
Cheng Zhang ◽  
Benyuan Huang ◽  
Xu Wang ◽  
Yulong Li ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Dielectric Loss ◽  
High Dielectric Constant ◽  
Dielectric Material ◽  
Epoxy Composite ◽  
Low Dielectric ◽  
High Dielectric

A novel skin–core structured fluorinated MWCNT nanofiller was prepared to fabricate epoxy composite with broadband high dielectric constant and low dielectric loss.

scholarly journals Crown ether-containing polyimides with high dielectric constant

RSC Advances ◽  
2017 ◽  
Vol 7 (38) ◽  
pp. 23309-23312 ◽  
Author(s):  
Ting Yang ◽  
Wenhui Xu ◽  
Xinwen Peng ◽  
Haoqing Hou
Keyword(s):  
Dielectric Constant ◽  
Dielectric Loss ◽  
Crown Ether ◽  
High Dielectric Constant ◽  
Low Dielectric ◽  
High Dielectric

Crown ether-containing polyimides possess high dielectric constant and low dielectric loss, without sacrificing other properties.

Sign in / Sign up

Export Citation Format

Share Document