Effect of Hf Doping on the Dielectric Properties of Barium Zirconate Titanate Ceramics

2011 ◽  
Vol 687 ◽  
pp. 263-268 ◽  
Author(s):  
Wei Cai ◽  
Chun Lin Fu ◽  
Jia Cheng Gao ◽  
Xiao Ling Deng ◽  
Wei Hai Jiang ◽  
...  
Keyword(s):  
Phase Transition ◽  
Dielectric Properties ◽  
Room Temperature ◽  
Solid State Reaction Method ◽  
Cubic Phase ◽  
Barium Zirconate ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
Barium Zirconate Titanate ◽  
Titanate Ceramics

Pure and Hf-doped BaZr0.2Ti0.8O3(short for BZT) ceramics are prepared by a conventional solid state reaction method. The crystal structure and dielectric properties of Hf-doped BZT ceramics have been investigated. The results indicate that Hf4+ ions have entered the unit cell maintaining the perovskite structure of solid solution and the pure and Hf-doped BZT ceramics are cubic phase. Addition of hafnium leads to the fall of the phase transition temperature and can decrease the dielectric loss of BZT ceramics at room temperature. When Hf content is more than 0.5 wt.%, the diffuseness of the phase transition enhances with the increasing of Hf content and when Hf content is 3 wt.%, the diffuseness of Hf-doped BZT ceramics is more than that of the pure BZT ceramics.

Structural and Dielectric Properties of XBaZr0.2Ti0.8O3-(1-x)BiFeO3 Solid Solution Ceramics

2014 ◽  
Vol 787 ◽  
pp. 261-266
Author(s):  
Wei Cai ◽  
Shi Xing Zhong ◽  
Chun Lin Fu ◽  
Gang Chen ◽  
Xiao Ling Deng
Keyword(s):  
Crystal Structure ◽  
Solid Solution ◽  
Dielectric Constant ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
Solid State Reaction Method ◽  
Barium Zirconate ◽  
Conventional Solid State Reaction ◽  
Barium Zirconate Titanate ◽  
Zirconate Titanate

xBaZr0.2Ti0.8O3-(1-x)BiFeO3(x=0, 0.3, 0.5, 0.7) solid solution ceramics were prepared by conventional solid-state reaction method. The crystal structure and dielectric properties ofxBaZr0.2Ti0.8O3-(1-x)BiFeO3ceramics have been investigated. The result indicates that the crystal structure of solid solution ceramics changes from rhobohedral to pseudocubic structure with the increase of barium zirconate titanate content. The room temperature dielectric constant of all samples decreases with the increasing of frequency. When the temperature is in the range of 30oC~150oC, the dielectric constant of all samples increases as temperature rises. In the same temperature range, the dielectric loss of BiFeO3ceramics increases with the rise of temperature and the dielectric loss ofxBaZr0.2Ti0.8O3-(1-x)BiFeO3(x=0.3~0.7) changes a little. The addition of barium zirconate titanate leads to the decrease of dielectric loss and leakage current for BiFeO3ceramics.

Dielectric Properties of Ba(Mg0.2/3Zn0.8/3Nb2/3)O3 and Ba1-xSrx(Mg0.2/3Zn0.8/3Nb2/3)O3 Microwave Ceramics

2007 ◽  
Vol 336-338 ◽  
pp. 272-274
Author(s):  
S.S. Cheng ◽  
J. Luo ◽  
Zhao Xian Xiong
Keyword(s):  
Dielectric Properties ◽  
Solid State ◽  
Resonant Frequency ◽  
Solid State Reaction ◽  
Solid State Reaction Method ◽  
Zero Temperature ◽  
Microwave Ceramics ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
Zn Ions

Microwave ceramics of Ba(Mg0.2/3Zn0.8/3Nb2/3)O3 and Ba1-xSrx(Mg0.2/3Zn0.8/3Nb2/3)O3 were synthesized with conventional solid-state reaction method. Dielectric properties of the samples were studied as functions of compositions and sintering temperatures. Experimental results show that a higher Q×f value is reached by substituting Zn ions with Mg ions and a near-zero temperature coefficient of resonant frequency is obtained by replacing Ba ions with Sr ions.

Investigations of PbxSr1-xTiO3 Thin Films and Ceramics for Microelectronic Applications

2004 ◽  
Vol 811 ◽  
Author(s):  
M. Jain ◽  
Yu.I. Yuzyuk ◽  
R.S. Katiyar ◽  
Y. Somiya ◽  
A.S. Bhalla ◽  
...  
Keyword(s):  
Thin Films ◽  
Phase Transition ◽  
Room Temperature ◽  
Sol Gel ◽  
Solid State Reaction Method ◽  
Phase Shifters ◽  
Conventional Solid State Reaction ◽  
Mode Behavior ◽  
Dielectric Devices ◽  
Pst System

ABSTRACTWe have investigated electrical and optical properties of the lead strontium titanate {(PbxSr1-x)TiO3 or PST} ceramic and dielectric properties of the thin films of PST at low and high frequencies. (PbxSr1-x)TiO3 compositions with × ≤ 0.4 are paraelectric at room temperature and exhibit ferroelectric phase transition below room temperature. Only one phase transition in the PST system (compared to three in BaxSr1-xTiO3) was recorded. The studies indicated that PST has potential for tunable microwave devices in the paraelectric phase. In the present studies, Pb0.3Sr0.7TiO3 (PST30) ceramic was prepared by the conventional solid-state reaction method and thin films of PST were prepared by sol-gel technique. Structural, microstructural, dielectric, and Raman measurements were performed on these samples. Sharp phase transition was observed in case of the ceramic by dielectric and Raman measurements at 283 K. Raman measurements revealed well-pronounced soft-mode behavior below the Curie temperature in PST ceramic. The thin film of PST deposited on lanthanum aluminate substrate was highly (100) oriented and showed dielectric maxima at ∼280 K, which was close to that in case of the bulk. Eight element coupled micro-strip phase shifters (CMPS) was fabricated on the PST film and tested in the frequency range of 15-17 GHz. The average figure of merit of 49 °/dB for PST30 film in the Ku band at 533 kV/cm suggests the potentiality of these films for high frequency tunable dielectric devices.

Effect of Gd Substitution on the Dielectric Properties and Magnetoelectric Effect of BiFeO3

2010 ◽  
Vol 150-151 ◽  
pp. 1470-1475
Author(s):  
Gui Lin Song ◽  
Tian Xing Wang ◽  
Cun Jun Xia ◽  
Chao Li ◽  
Fang Gao Chang
Keyword(s):  
Dielectric Constant ◽  
Rare Earth ◽  
Dielectric Loss ◽  
Room Temperature ◽  
Magnetoelectric Effect ◽  
Solid State Reaction Method ◽  
Impurity Phase ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
Dielectric Relaxation Process

Multiferroic Bi1-xGdxFeO3(x=0, 0.05, 0.1, 0.15, 0.2) ceramics were prepared by conventional solid state reaction method. For all the samples prepared, they exhibit magnetoelectric effect at room temperature, and the dielectric constant and dielectric loss decrease with increasing frequency in the range from 10000Hz to 1 MHz from a typical orientational dielectric relaxation process. It has been found that both dielectric constant and dielectric loss are strongly dependent on the Gd3+ content. And substitution of Bi with rare earth Gd helps to eliminate the impurity phase in BiFeO3 ceramics.,

Dielectric Properties of Zr-Doped CaCu3Ti4O12 Ceramics

2008 ◽  
Vol 368-372 ◽  
pp. 129-131
Author(s):  
Yong He ◽  
Ke Pi Chen ◽  
Dong Yu Liu ◽  
Zong De Liu
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Solid State ◽  
Impedance Spectroscopy ◽  
Solid State Reaction ◽  
Solid State Reaction Method ◽  
Conventional Solid State Reaction ◽  
Obvious Effect ◽  
Reaction Method ◽  
Microstructure Characteristic

CaCu3(Ti1-xZrx)O12 ceramics (x = 0.02, 0.04, 0.06, 0.08) were prepared by the conventional solid-state reaction method. Phase compositions, microstructure and dielectric properties were examined by XRD, SEM and impedance spectroscopy, respectively. The experimental results indicated that there is no obvious effect on microstructure characteristic by substituting Zr4+ for Ti4+. It was found that the values of the dielectric constant for all of the samples dropped into the order of 102, which is significantly lower than the order of 105 that of normally reported in the literature. It was suggested that the presence of impurity phases played an important role for the degeneracy of dielectric properties.

Structural, magnetic and dielectric properties of the Aurivillius phase Bi6Fe2−xMnxTi3O18 (0 ≤ x ≤ 0.8)

RSC Advances ◽  
2014 ◽  
Vol 4 (87) ◽  
pp. 46704-46709 ◽  
Author(s):  
Xuzhong Zuo ◽  
Jie Yang ◽  
Bin Yuan ◽  
Dongpo Song ◽  
Xianwu Tang ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Solid State ◽  
Solid State Reaction ◽  
Solid State Reaction Method ◽  
Aurivillius Phase ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
Magnetic And Dielectric Properties

The n = 5 Aurivillius phase ceramics Bi6Fe2−xMnxTi3O18 (BFMTO) (0 ≤ x ≤ 0.8) were synthesized with a conventional solid-state reaction method.

Study on the Property of Bi2(Mg2/3Nb1.1833Sn0.15)O7 Dielectric Ceramics Doped with Li2CO3

2012 ◽  
Vol 549 ◽  
pp. 749-752
Author(s):  
Hai Tang Hua ◽  
Xin You Huang ◽  
Zhi Wen Zhu ◽  
Yin Qun Hua ◽  
Yan Li
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Solid State ◽  
Dielectric Loss ◽  
Solid State Reaction ◽  
Piezoelectric Ceramics ◽  
Solid State Reaction Method ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
Dielectric Ceramics

(Bi2-xLix) (Mg2/3Nb1.1833Sn0.15)O7 piezoelectric ceramics were prepared by conventional solid state reaction method. The microstructure and dielectric properties of dielectric ceramics were studied which was doped by different amount of Li2CO3. The experiment results showed that the density of the ceramics would decrease, but have little effect on the microstructure of the ceramics when the amount of the Li2CO3 doped increases. With the increasing of Li2CO3 doped, the dielectric constant(εr) and dielectric loss(tanδ) of dielectric ceramics first decreases and then increases. When tested in 1MHz frequency, the piezoelectric ceramics display the optimum properties tanδ is 0.00009, εr is 163 while Li2CO3 doped amount is 0.05 mol%.

Structural and Dielectric Properties of Na0.5Bi0.5TiO3 Ferroelectric Ceramics

2012 ◽  
Vol 585 ◽  
pp. 219-223
Author(s):  
Rekha Kumari ◽  
N. Ahlawat ◽  
Ashish Agarwal ◽  
M. Sindhu ◽  
N.N. Ahlawat
Keyword(s):  
Dielectric Properties ◽  
Solid State Reaction Method ◽  
Wide Frequency Range ◽  
Ferroelectric Ceramics ◽  
Frequency Range ◽  
X Ray Diffraction ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
X Ray ◽  
Different Temperatures

Na0.5Bi0.5TiO3 (NBT) ceramics were synthesized by conventional solid state reaction method. Structural and dielectric properties of these ceramics were investigated. Crystalline phase of sintered ceramics was investigated by X-ray diffraction (XRD). The Rietveld refinement of powder X-ray diffraction revealed that the prepared ceramics exhibit the rhombohedral space group R3c. Dielectric properties of Na0.5Bi0. analyzer.5TiO3 (NBT) ceramics were studied at different temperatures in a wide frequency range using impedance

Photoresponsive character in double-doped La2/3(Ca2/3Sr1/3)1/3MnO3 thin film

2005 ◽  
Vol 83 (7) ◽  
pp. 699-704 ◽  
Author(s):  
Y. Wang ◽  
R Ren ◽  
C Chen ◽  
D Ren ◽  
K Jin ◽  
...  
Keyword(s):  
Thin Film ◽  
Phase Transition ◽  
Solid State ◽  
Room Temperature ◽  
Rf Magnetron Sputtering ◽  
Solid State Reaction Method ◽  
Metallic State ◽  
Reaction Method ◽  
Temperature Range ◽  
Cw Laser

A Ca, Sr double-doped La2/3(Ca2/3Sr1/3)1/3MnO3 thin film with a thickness of about 60~nm was deposited on (100) LaAlO3 substrates using the RF magnetron sputtering method from the bulk compound prepared using the solid-state reaction method. The experimental results show that a phase transition from the ferromagnetic metallic state to the paramagnetic insulating state occurs at 341 K (near to Tp, the highest peak temperature). The R–T curve deviation of the thin film with the application of CW laser is dramatic in the low-temperature range and Δ R/R is positive. At 276 K, the Δ R/R reaches the maximum, about 41 %, and the temperature of the photo-induced resistance maximum of this double-doped thin film appears near to room temperature range, which offers a new method for the application of CMR photo-electric devices.PACS Nos.: 78.66.–w, 81.07–b

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