Internal-strain-controlled Tungsten Bronze Structural Ceramic for 5G Millimeter-wave Metamaterials

2021 ◽  
Author(s):  
Lingxia Li ◽  
Xubin Wang ◽  
Weijia Luo ◽  
Shun Wang ◽  
Tian Yang ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Millimeter Wave ◽  
Power Dissipation ◽  
High Dielectric Constant ◽  
Tungsten Bronze ◽  
Temperature Stability ◽  
Internal Strain ◽  
Critical Factors ◽  
Structural Ceramic ◽  
High Dielectric

Miniaturization, power dissipation and temperature stability are the most critical factors restricting the microwave use of ceramic-based devices. How to balance them, especially for the ceramics with high dielectric constant,...

THE STUDY OF HIGH DIELECTRIC CONSTANT MECHANISM OF La-DOPED Ba0.67Sr0.33TiO3 CERAMICS

2018 ◽  
Vol 25 (02) ◽  
pp. 1850056
Author(s):  
JING XU ◽  
BO HE ◽  
HAN XING LIU
Keyword(s):  
Dielectric Constant ◽  
Rare Earth ◽  
High Dielectric Constant ◽  
Temperature Stability ◽  
Current Voltage ◽  
Microstructure Model ◽  
Bst Ceramics ◽  
High Dielectric ◽  
Rare Earth La ◽  
La Doped

It is a common and effective method to enhance the dielectric properties of BST ceramics by adding rare-earth elements. In this paper, it is important to analyze the cause of the high dielectric constant behavior of La-doped BST ceramics. The results show that proper rare earth La dopant ([Formula: see text]) may greatly increase the dielectric constant of BST ceramics, and also improve the temperature stability, evidently. According to the current–voltage ([Formula: see text]–[Formula: see text]) characteristics, the proper La-doped BST ceramics may reach the better semiconductivity, with the decrease and increase in La doping, the ceramics are insulators. By using the Schottky barrier model and electric microstructure model to find the surface or grain boundary potential barrier height, the width of the depletion layer and grain size do play an important role in impacting the dielectric constant.

X7R type lead complex perovskite ferroelectric ceramics with high dielectric constant

1998 ◽  
Vol 13 (2) ◽  
pp. 253-256 ◽  
Author(s):  
Lijian Ruan ◽  
Longtu Li ◽  
Zhilun Gui
Keyword(s):  
Dielectric Constant ◽  
High Dielectric Constant ◽  
Temperature Stability ◽  
Ferroelectric Ceramics ◽  
Complex Perovskite ◽  
Two Phase ◽  
Dielectric Ceramics ◽  
High Dielectric ◽  
Lead Complex ◽  
Sintering Method

A new X7R type dielectric ceramics for the PMN-BT-PT system with a high dielectric constant (4832) and a low firing temperature (1100–1130 °C) was prepared by the mixed-sintering method. The results of XRD, SEM, EDAX, and dielectric measurements showed that the dielectric ceramics is a two-phase composite with the high dielectric constant originating from the ferroelectric relaxor, and the temperature stability of the dielectric properties from two-phase coexistence.

Dielectric ceramics in the BaO–Sm2O3–TiO2–Ta2O5 quaternary system

2000 ◽  
Vol 15 (1) ◽  
pp. 125-129 ◽  
Author(s):  
X. M. Chen ◽  
Z. Y. Xu ◽  
J. Li
Keyword(s):  
Dielectric Constant ◽  
Temperature Coefficient ◽  
Quaternary System ◽  
High Dielectric Constant ◽  
Tungsten Bronze ◽  
Complex Phase ◽  
Low Dielectric ◽  
Unknown Phase ◽  
Dielectric Ceramics ◽  
High Dielectric

Dielectric ceramics in the BaO–Sm2O3–TiO2–Ta2O5 quaternary system were prepared and characterized for five typical compositions: BaSm5Ti7Ta3O30, Ba2Sm4Ti6Ta4O30, Ba3Sm3Ti5Ta5O30, Ba4Sm2Ti4Ta6O30, and Ba5SmTi3Ta7O30. The latter three compositions tended to form the tungsten–bronze phase, and the ceramics based on these compositions had a high dielectric constant (134–175) and a low dielectric loss (on the order of 10−3) but a larger temperature coefficient of the dielectric constant. Meanwhile, the former two compositions generally had a more complex phase constitution, containing the tungsten–bronze phase combined with some unknown phase, and a relatively small temperature coefficient of the dielectric constant in the temperature range of 20 to 85 °C could be achieved in these two compositions.

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.

Enhanced performance of supercapacitors by constructing a “mini parallel-plate capacitor” in an electrode with high dielectric constant materials

2020 ◽  
Vol 8 (32) ◽  
pp. 16661-16668
Author(s):  
Huayao Tu ◽  
Shouzhi Wang ◽  
Hehe Jiang ◽  
Zhenyan Liang ◽  
Dong Shi ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Carbon Fiber ◽  
Parallel Plate ◽  
Sandwich Structure ◽  
High Dielectric Constant ◽  
Parallel Plate Capacitor ◽  
Plate Capacitor ◽  
Fiber Metal ◽  
High Dielectric ◽  
Mini Plate

The carbon fiber/metal oxide/metal oxynitride layer sandwich structure is constructed in the electrode to form a mini-plate capacitor. High dielectric constant metal oxides act as dielectric to increase their capacitance.

Sign in / Sign up

Export Citation Format

Share Document