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International Journal of Minerals,Metallurgy and Materials 2012年第8期19卷 762-767页

作者： Shun-hua Xiao Wei-fen Jiang Co11ege of Chemistry and Bioengineering Key Laboratory of New Processing Technology for Nonferrous Metals and Materials (Ministry of Education) Guilin University of Technology Guilin 541004 China Department of Mathematics and Information Science North China Institute of Water Conservancy and Hydroelectric Power Zhengzhou 450011 China

barium strontium titanate （Ba0.5Sr0.5TiO3, BST）/silicon nanoporous pillar array （Si-NPA） thin films were prepared by a spin-coating/annealing technique based on Si-NPA with micro/nano-structure. Both the isomer conversion of acetylacetone and the network structure combined by enol and Ti-alkoxide facilitate the formation of the BST sol and the subsequent crystallization. Before the perovskite BST begins to form, the intermediate phase （Ba, Sr）Ti2OsCO3 is found. The boundary between BST and Si-NPA is of clarity and little interface diffusion, disclosing that Si-NPA is an ideal template substrate in the preparation of multifunctional composite films.

关键词： barium strontium titanate silicon nanoporous materials composite films sol-gel process

Glass modified barium strontium titanate ceramics for energy storage capacitor at elevated temperatures

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Journal of Materiomics 2019年第4期5卷 641-648页

作者： Zong-Yang Shen Yu Wang Yanxue Tang Yuanying Yu Wen-Qin Luo Xingcai Wang Yueming Li Zhumei Wang Fusheng Song Energy Storage and Conversion Ceramic Materials Engineering Laboratory of Jiangxi Province China National Light Industry Key Laboratory of Functional Ceramic MaterialsSchool of Materials Science and EngineeringJingdezhen Ceramic InstituteJingdezhen333403China Key Laboratory of Optoelectronic Material and Device Shanghai Normal UniversityShanghai200234China Chengdu Hongming UESTC Electronic New Materials Co. Ltd.Chengdu610100China

A glass with composition of B_(2)O_(3)-Bi_(2)O_(3)-SiO_(2)-CaO-BaO-Al_(2)O_(3)-ZrO_(2)(BBSZ)modified Ba_(x)Sr_(1-x)TiO_(3)(BST,x=0.3 and 0.4)ceramics were prepared by a conventional solid state reaction method abided by a formula of BST+y%BBSZ(y=0,2,4,7,and 10,in mass).The effect of BBSZ glass content on the structure,dielectric properties and energy storage characteristics of the ceramics was *** dielectric constant reduced but the endurable electrical strength enhanced due to the BBSZ glass addition in BST *** particular,the dielectric loss of the ceramics at elevated temperature(e.g.200℃)can be strongly suppressed from tanδ>20%to tanδ<3% after BBSZ glass *** Ba_(0.3)Sr_(0.7)TiO_(3)+2%BBSZ ceramics,an optimized energy storage density(γ=0.63 J/cm^(3))and efficiency(η=91.6%)under an applied electric field of 160 kV/cm was obtained at room ***,the temperature dependent polarization-electric field(P-E)hysteresis loops were measured to evaluate the energy storage characteristics of the ceramics potential for high voltage capacitor application at elevated temperatures.

关键词： barium strontium titanate Glass modification Energy storage Ceramic capacitor

Dielectric properties and point defect behavior of antimony oxide doped Ti deficient barium strontium titanate ceramics

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Transactions of Nonferrous Metals Society of China 2017年第12期27卷 2656-2662页

作者： Chen ZHANG Zhi-xin LING Gang JIAN Fang-xu CHEN Provincial Key Lab of Advanced Welding Technology Jiangsu University of Science and Technology Zhenjiang 212003 China

The microstructures and dielectric properties of Sb2O3-doped Ti deficient barium strontium titanate ceramics prepared by solid state method were investigated with non-stoichiometric level and Sb2O3content by SEM,XRD and LCR measure *** is found that with the increase ofδ,(Ba0.75Sr0.25)Ti1-δO3-2δceramics transform from single phase solid solutions with typical cubic perovskite structure to multiphase compounds while(Ba0.75Sr0.25)Ti0.998O2.996ceramics remain to be single-phase with the increasing *** distortion of the ABO3perovskite lattice caused by VTi″″and VO..induces the drop of Curie temperature and the rise of relative dielectric constant in(Ba0.75Sr0.25)Ti1-δO3-2δceramics with increasingδ*** orientation of VO??elastic dipoles results in the domain-wall pinning and thus the reduction of the dielectric *** increasing Sb2O3content,the relative dielectric constant,dielectric constant maximum and Curie temperature of(Ba0.75Sr0.25)Ti0.998O2.996ceramics decrease dramatically while the dielectric loss increases.

关键词： barium strontium titanate defects dielectric properties non-stoichiometric ceramics

Dielectric properties and phase transitions of La_2O_3- and Sb_2O_3-doped barium strontium titanate ceramics

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Transactions of Nonferrous Metals Society of China 2012年第11期22卷 2742-2748页

作者：张晨曲远方江苏科技大学江苏省先进焊接技术重点实验室镇江212003 天津大学先进陶瓷与加工技术教育部重点实验室天津300072

The dielectric properties and phase transition characteristics of La2O3- and Sb2O3-doped barium strontium titanate ceramics prepared by solid state route were investigated. The microstructure was identified by X-ray diffraction method and scanning electron microscope was also employed to observe the surface morphologies. It is found that （La,Sb）-codoped barium strontium titanate ceramics exhibit typical perovskite structure and the average grain size decreases dramatically with increasing the content of Sb2O3. Both La3＋ ions and Sb3＋ ions occupy the A-sites in perovskite lattice. The dielectric constant and dielectric loss of barium strontium titanate based ceramics are obviously influenced by La2O3 as well as Sb2O3 addition content. The tetragonal-cubic phase transition of La2O3 modified barium strontium titanate ceramics is of second order and the Curie temperature shifts to lower value with increasing the La2O3 doping content. The phase transition of （La,Sb）-codoped barium strontium titanate ceramics diffuses and the deviation from Curie-Weiss law becomes more obvious with the increase in Sb2O3 concentration. The temperature corresponding to the dielectric constant maximum of （La,Sb）-codoped barium strontium titanate ceramics decreases with increasing the Sb2O3 content, which is attributed to the replacement of host ions by the Sb3＋ ions.

关键词： barium strontium titanate La2O3 Sb2O3 perovskite ceramics dielectric properties phase transition

Preparation and Characterization of Compositionally Graded Epitaxial barium strontium titanate Thin Films via Scanning Probe Microscopy

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Preparation and Characterization of Compositionally Graded E...

Ultrahigh frequency tunability of aperture-coupled microstrip antenna via electric-field tunable BST

The 3～〔rd〕International Conference on High-Performance Ceramics(CICC-3)（2）

作者： Haydn Chen C.L.Mak C.L.Choy Department of Physics and Materials Science City University of Hong Kong Hong Kong Department of Applied Physics and Materials Research Centre The Hong Kong Polytechnic University Hong Kong Department of Applied Physics and Materials Research Centre The Hong Kong Polytechnic University Hong Kong

＜正＞ Epitaxially graded barium strontium titanate （BaxSr1-x）TiO3 （x = 0.75,0.8,0.9,1.0, abbreviated as BST75, BST80, BST90 and BTO respectively） thin films were fabricated by pulsed laser deposition method on the （La0.7Sr0.3）MnO3 （LSMO）/LaAlO3 （LAO） single crystal substrate. Scanning probe microscopy with a contact mode was used to characterize the temperature dependence of polarization from room temperature to 140℃. Results indicated that the piezo-response signal of the BST graded films had an obvious change with temperature, and that the graded structures had a flatter temperature dependence of permittivity. Furthermore, the contrasts of the SPM images were lower for the ferroelectric - paraelectric （F-P） phase transition temperatures of BST 75, BST 80, and BST90, but higher for the F-P transition temperature of BTO.

关键词： barium strontium titanate Thin film Scanning force microscopy.

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Chinese Physics B 2015年第12期24卷 568-571页

作者：杜洪磊薛倩高小洋姚凤蕊卢世阳汪业龙刘春恒张永成吕跃广李山东 College of Physics Laboratory of Fiber Materials and Modern Textile the Growing Base for State Key Laboratory and Key Laboratory of Photonics Materials and Technology in Universities of Shandong Qingdao University Department of Physics School of Science Harbin Institute of Technology Northern Institute of Electronic Equipment of China National Laboratory of Solid State Microstructures Nanjing University

A composite ceramic with nominal composition of 45.0 wt%（Ba0.5Sr0.5）TiO3–55.0 wt%MgO（acronym is BST–MgO） is sintered for fabricating a frequency reconfigurable aperture-coupled microstrip antenna. The calcined BST–Mg O composite ceramic exhibits good microwave dielectric properties at X-band with appropriate dielectric constant εr around85, lower dielectric loss tan δ about 0.01, and higher permittivity tunability 14.8% at 8.33 k V/cm. An ultrahigh E-field tunability of working frequency up to 11.0%（i.e., from 9.1 GHz to 10.1 GHz with a large frequency shift of 1000 MHz）at a DC bias field from 0 to 8.33 k V/cm and a considerably large center gain over 7.5 d B are obtained in the designed frequency reconfigurable microstrip antenna. These results demonstrate that BST materials are promising for the frequency reconfigurable antenna.

关键词： barium strontium titanate E-field tunability frequency reconfigurable antennas microstrip an tenna

Dielectric properties of BaMg_(1/3)Nb_(2/3)O_(3) doped Ba_(0.45)Sr_(0.55)TiO_(3) thin films for tunable microwave applications

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Journal of Advanced Dielectrics 2015年第4期5卷 21-29页

作者： Fikadu Alema Konstantin Pokhodnya Center for Nanoscale Science and Engineering North Dakota State University Fargo ND 58108USA Agnitron Technology Incorporated Eden Prairie MN 55344USA

Ba(Mg_(1/3)Nb_(2/3))O_(3)(BMN)doped and undoped B_(0.45)Sr_(0.55)TiO_(3)(BST)thin films were deposited via radio frequency magnetron sputtering on PUTiO_(2)/SiO_(2)/Al_(2)O_(3) *** surface morphology and chemical state analyses of the films have shown that the BMN doped BST film has a smoother surface with reduced oxygen vacancy,resulting in an improved insulating properties of the BST *** tunability,loss,and leakage current(LC)of the undoped and BMN doped BST thin flms were *** BMN dopant has remarkably reduced the dielectric loss(~38%)with no significant effect on the tunability of the BST film,leading to an increase in figure of merit(FOM).This is attributed to the opposing behavior of large Mg2+whose detrimental effect on tunability is partially compensated by small Nb5+as the two substitute Ti4+in the *** coupling between Mg″_(Ti)and V_(o)charged defects suppresses the dielectric loss in the film by cutting electrons from hopping between Ti *** LC of the films was investigated in the temperature range of 300-450K.A reduced LC measured for the BMN doped BST film was correlated to the formation of defect dipoles from Mg″_(Ti),V_(o)and Nb_(Ti) charged *** carrier transport properties of the films were analyzed in light of Schottky thermionic emission(SE)and Poole-Frenkel(PF)enmission *** result indicated that while the carrier transport mechanism in the undoped film is interface limited(SE),the conduction in the BMN doped film was dominated by bulk processes(PF).The change of the conduction mechanism from SE to PF as a result of BMN doping is atributed to the presence of uncoupled Nb_(Ti) stting as a positive trap center at the shallow donor level of the BST.

关键词： barium strontium titanate sputtering frreletric thin film tunability leakage current permitivity loss figure of merit defect dipole

Dispersityonbarium-strontium titanate Nanopowders by Microwave-hydrothermal Processing

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DispersityonBarium-strontium Titanate Nanopowders by Microwa...

Structure and dielectric properties of NBT-xBT-ST lead-free ceramics for energy storage

2014中国功能材料科技与产业高层论坛

作者： Jie Chen Mingchao Che Feng Yan School of Material Science and Engineering Xi’an University of Science and Technology

Through the microwave-hydrothermal processing at 70℃in 10 min,barium strontium ti tanate（BST）nanopowders are prepared by using butyl-titanate,barium nitrate and strontium nitrate as raw *** kinds ofdispersants namely polyethylene glycol 6000 and OP-10 are added *** effects of the different dispersant and dosage on the crystal phase and microstructure are studied by X-ray diffraction and *** disperse mechanism *** results show that the dispersion effect ofOP-10 is better than that of the polyethylene *** long chain of OP-10 can be used to disperse nano-powders through a space steric hindrance ***-dispersed barium strontium ti tanate nano-powders are obtained when mass percent ratio of dispersant（OP-10）is 5%.

关键词： barium strontium titanate dispersity OP10 polyethylene glycol 6000

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Journal of Advanced Dielectrics 2018年第6期8卷 3-7页

作者： Wen-Qin Luo Zong-Yang Shen Yuan-Ying Yu Fu-Sheng Song Zhu-Mei Wang Yue-Ming Li Energy Storage and Conversion Ceramic Materials Engineering Laboratory of Jiangxi Province China National Light Industry Key Laboratory of Functional Ceramic Materials School of Materials Science and Engineering Jingdezhen Ceramic Institute Jingdezhen 333403P.R.China

(0:74-x)(Na_(0.5)Bi_(0.5))TiO_(3)-xBaTiO_(3)-0.26SrTiO_(3)(x=0~0.1)(abbreviated as NBT-xBT-ST)lead-free ceramics were fabricated by a solid-state reaction *** effect of Ba doping amount x on the structure and energy storage properties of NBT-xBT-ST ceramics were *** the NBT-xBT-ST ceramics showed single perovskite structure with a pseudocubic *** doping effectively suppressed grain growth,in favor of forming small and uniform *** ceramics with a composition of x=0.04,an optimized energy storage density(γ=0.47 J/cm^(3))and efficiency(η=48:67%),under an applied electric field of 50 kV/cm,should be a candidate for solid-state compact pulsed power capacitor materials.

关键词： Sodium bismuth titanate barium strontium titanate energy storage ceramics compact pulsed power

Preparation and Characterization of La2O3Doped Ba0.3Sr0.7TiO3Perovskite Ceramics of Varied Sintering Temperature and Doping

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Advances in Materials Physics and Chemistry 2020年第11期10卷 253-262页

作者： Sanchita Dewanjee Rajib Chandra Das Muhammed Yusuf Miah Department of Applied Chemistry and Chemical Engineering Noakhali Science and Technology University Noakhali Bangladesh

In order to explore new application opportunities of barium strontium titanate (BST) ceramic composite by modifying the conventional ferroelectric properties of BST through La2O3 doping in BST matrix sintered at different temperature was investigated in this current study. Unadulterated Ba0.3Sr0.7TiO3 (BST) matrix was prepared from BaTiO3 (99.95%) and SrTiO3 (99.95%) taken in stoichiometric extents which later doped by La2O3 (99.99%) in varying extents (0.05 g, 0.10 g and 0.15 g) exploiting solid state reaction route. Doping caused drag effect for the penetration of impurities and sintering temperature helped the impurities migration to BST. Dielectric constant gets lower with rising of frequency, as electrons do not get enough time to polarize at high frequency. Dielectric constant and conductance are found maximum for the sample (0.1 g La2O3 doped BST) sintered at 1460°C and reverse is found in impedance analysis. These electrical properties showed visible frequency dependent response irrespective of sintering temperature and doping.

关键词： barium strontium titanate Lanthanum Oxide Ceramics Dielectric Constant Conductivity Impedance