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Influence of KF substitution on the ferroelectric phase transition of lead titanate single crystals studied by Brillouin light scattering

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Journal of Advanced Dielectrics 2015年第2期5卷 47-52页

作者： Seonhyeop Shin Jae-Hyeon Ko Shinya Tsukada Yukikuni Akishige Krystian Roleder Daniel Rytz Department of Physics Hallym UniversityHallymdaehakgil 39 ChuncheonGangwondo 200-702Republic of Korea Faculty of Education Shimane University Matsue-ShiShimane 690-8504Japan Institute of Physics University of Silesia ulica Uniwersytecka 4PL-40-007 KatowicePoland Forschungsinstitut für mineralische und metallische Werkstoffe Edelsteine/Edelmetalle GmbH(FEE)Struthstraβe 2 D-55743 Idar-ObersteinGermany

The elastic properties of KF-substituted perovskite lead titanate(PbTiO_(3))were investigated by dielectric measurements and Brillouin light *** ferroelectric phase transition occurred at substantially lower temperature due to KF substitution,which was attributed to the modification of the covalency in Pb–O and Ti–O *** longitudinal acoustic(LA)mode of KF-substituted PbTiO_(3) showed a frequency softening in the paraelectric phase,which was accompanied by increasing acoustic *** indicated that polarization fluctuations responsible for the acoustic anomalies were enhanced by KF substitution.

关键词： lead titanate KF-substitution elastic property Brillouin scattering

THE PREPARATION AND PHOTOCATALYTIC ABILITY OF lead titanate

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Transactions of Tianjin University 1995年第1期1卷 62+59-62页

作者：戎谊梅古风才王俊珍单志兴曾淑兰

he perovskite-type PbTiO3 has been synthesized by the method of mixed oxides. The appropriate conditions for preparing have been reported. The obtained PbTiO3 powder is pure and fine. The decolorization of dyes in a PbTiO3 suspension system is over 90%. In this paper the photocatalytic ability of PbTiO3 and the factors of influence are discussed.

关键词： lead titanate method of mixed oxides photocatalytic activity decolorization

Semi-empirical estimation for enhancing negative thermal expansion in PbTiO_(3)-based perovskites

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International Journal of Minerals,Metallurgy and Materials 2022年第4期29卷 783-786页

作者： Tao Yang Longlong Fan Yilin Wang Kun Lin Jun Chen Xianran Xing Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Solid State ChemistryDepartment of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China College of Physics and Materials Science Tianjin Normal UniversityTianjin 300387China Institute of Advanced Materials Jiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjing 211816China

Generally,most materials expand when heated and contract when cooled,whereas negative thermal expansion(NTE)materials are very *** a typical NTE material,PbTiO_(3) and related compounds have drawn particular interest in recent *** discovery of an enhanced NTE system in PbTiO_(3) is beneficial to deepen our understanding of its mechanism and regulate its *** present,the method of discriminating an enhanced NTE material based on PbTiO_(3) is not ***,we propose a semi-empirical method through evaluating the average lattice distortion in related systems to estimate the relative coefficient of thermal expansion *** rationality of the method was verified by the analysis of the 0.6PbTiO_(3)-0.4Bi(Ga_(x)Fe_(1-x))O_(3) *** far,all PbTiO_(3)-based compounds with enhanced NTE conform well to this *** method provides the possibility to find more enhanced NTE PbTiO_(3)-based materials.

关键词： enhanced negative thermal expansion crystal structure lead titanate spontaneous polarization

High visible light photocatalytic activities obtained by integrating g-C_(3)N_(4) with ferroelectric PbTiO_(3)

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Journal of Materials Science & Technology 2021年第15期74卷 128-135页

作者： Tingting Xu Ping Niu Shulan Wang Li Li Department of Chemistry School of ScienceNortheastern UniversityShenyang110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang110819China

Graphitic carbon nitride(g-C_(3)N_(4))with the merits of high visible light absorption,proper electronic band structure with high conduction band edge and variable modulation,is viewed as a promising photocatalyst for practical *** alleviate its high recombination rate of photo-excited charge carriers and maximize the photocatalytic performances,it is paramount to design highly effective transfer channels for photo-excited charge *** materials can have the charge carriers transport in opposite directions owing to the internal spontaneous polarization,which may be suitable for constructing the heterostructure with g-C_(3)N_(4)for efficient charge *** by this concept,herein ferroelectric PbTiO_(3),which can be the visible-light absorber,is coupled with g-C_(3)N_(4)to construct PbTiO_(3)/g-C_(3)N_(4)heterostructure with close contact via Pb–N bond by the facile post thermal *** optimized Pb TiO_(3)/g-C_(3)N_(4)heterostructure exhibited excellent photocatalytic and photoelectrochemical activities under visible light ***,the simultaneous application of ultrasound-induced mechanical waves can further improve its photocatalytic activities through reinforcing the built-in piezoelectric *** work proposes a widely applicable strategy for the fabrication of high-performance ferroelectric based photocatalysts and also provides some new ideas for developing the understanding of ferroelectric photocatalysis.

关键词： Photocatalysis Ferroelectric Piezoelectric Carbon nitride lead titanate

Structure and Shape Control of Hydrothermally Synthesized PbTiO_3 --Effects of pH and Complexing Agents

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Chemical Research in Chinese Universities 2003年第1期19卷 1-5页

作者： XIAO Li-hua CHEN Dai-rong 等 StateKeyLaboratoryforOxoSynthesisandSelectiveOxidation LanzhouInstituteofChemicalPhysicsChineseAcademyofSciencesLanzhou730000P.RChinas DepartmentofChemistry ShandongUniversity

Tabular PE PbTiO 3, spherical PY PbTiO 3, and acicular PX PbTiO 3 powders were hydrothermally synthesized from triethanolamine(TEA) complexed precursor; clubbed PE PbTiO 3 powders were obtained from diethanolamine(DEA) complexed precursor. The effects of pH of the hydrolyzation as well as complexing agents including TEA, DEA, and MEA(monoethanolamine) on the structure and the morphology of PbTiO 3 powders are discussed. The optimal conditions for hydrothermal syntheses of acicular and clubbed PbTiO 3 powders have been established. The products were characterized by means of XRD, TEM and other techniques.

关键词： lead titanate Hydrothermal synthesis Complexing agent

The effects of N-doping and oxygen vacancy on the electronic structure and conductivity of PbTiO_3

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Journal of Semiconductors 2015年第4期36卷 30-35页

作者：牛培江闫金良孟德兰 School of Physics and Optoelectronic Engineering Ludong University

By using spin-polarized density functional theory calculations, the electron density differences, band structures and density of states of p-type N-doped PbTiO3 have been studied. In addition, the oxygen vacancy in N-doped PbTiO3 is also discussed. After the nitrogen dopant is introduced into the crystal, the N-doped PbTiO3 system is spin-polarized, the spin-down valance bands move to a high energy level and the Fermi energy level moves to the top of the valance bands, finally the band gap is narrowed. In this process, the N-doped PbTiO3 shows typical p-type semiconductor characteristics. When an oxygen vacancy and N impurity coexist in PbTiO3, there is no spin-polarized phenomenon. The conduction bands move downward and the acceptors are found to be fully compensated. The calculation results are mostly consistent with the experimental data.

关键词： semiconductor doping electric properties optical band gaps optical properties lead titanate

Incorporation of dysprosium ions into PbTiO_(3) ferroelectric ceramic system

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Journal of Advanced Dielectrics 2015年第1期5卷 29-33页

作者： A.Peláiz-Barranco Y.Mendez-González Jinfei Wang Tongqing Yang Facultad de Física-IMRE Universidad de La Habana.San Lázaro y L Vedado.La Habana 10400Cuba Functional Materials Research Laboratory College for Materials Science and Engineering Tongji University 4800 CaoanShanghai 201804P.R.China

A structural analysis concerning the incorporation of dysprosium into A-and/or B-sites of the lead titanate is *** two"boundary"refinements are presented,i.e.,Dy^(2+)substitutes for Pb^(2+)(Dy^(3+)substitutes for Ti^(4+))and Dy^(3+)substitutes for Pb^(2+)(Dy^(3+)substitutes for Ti^(4+)).The results offer quantitative information about the incorporation into both crystallographic *** increase of Dy^(3+)fraction into B-site provides the increase of the Ti^(4+)atomic displacement along the[001]direction and the tetragonal distortion.

关键词： lead titanate lanthanides perovskites crystalline structure

Studies of dielectric and piezoelectric properties of PbTi_(0.8-x)Te_(0.2)Gd_(x)O_(3)nano ceramics prepared by high energy ball milling

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Journal of Advanced Dielectrics 2019年第2期9卷 45-49页

作者： S.K.Sinha S.Kumari R.K.Chaudhary Department of Physics Birla Institute of TechnologyMesra Patna CampusPatna-800014India Department of Physics National Institute of Technology Jamshedpur-831016India

Incorporation of Te and Gd were done based on the stoicheometric formula PbTi_(0.8-x)Te_(0.2)Gd_(x)O_(3)(PTTeG).TG characterization of green powder revealed the completion of solid state reaction at temperature 450℃.XRD of modified PTTeG powders milled for 10 h was found most suitable as it gives pure single-phase tetragonal *** constant was found as 25 43 at curie temperature of 480℃in the case of 5 wt.%of Gd in *** Coefficient was found as 241×10^(-12)C/N at 39 Kv/cm of poling *** results obtained were comparable and even better than so far reported in similar kind of materials.

关键词： lead titanate high energy ball milling chalcogenide tellurium dielectrics.

Structural Morphological and Dielectric Properties of Pb1-xNixTiO3 Doped with Ni

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Open Journal of Applied Sciences 2016年第11期6卷 796-813页

作者： A. Tawfik O.M. Hemeda D.M. Hemeda R. Shady M. Barakat Faculty of Science Physics Department Tanta University Tanta Egypt Oklat Al-Skoor Fac. of Science & Arts Physics Department Qassim University Qassim Saudi Arabia

In this paper, we have reported a conformable PbTiO3 ceramics doped with Ni by standard double sintering technique as well as chemical co-precipitation method which were successfully synthesized by means of carefully controlled processing parameters. Single phase formation was confirmed through X-Ray Diffraction (XRD) analysis, IR spectroscopy, SEM micrograph and TEM images. Discussion and comparison between both preparation methods were made on the basis of observed results. The tetragonality c/a decreased from 1.049 to 1.0276 for ceramic samples and decreased from 1.06519 to 1.0365 for co-precipitation samples by increasing Ni content. TEM images show small ferroelectric domains of about 3 to 14 nm for the co-precipitation sample and 26 to 48 nm for the ceramic samples. The SEM of co- precipitation samples shows that the microstructure is very dense. The behavior of ε identifies that our samples are nonrelaxor. Increasing the Ni concentration increases the value of dielectric constant and the Tc is shifted to lower temperature.

关键词： lead titanate Co-Precipitation Method Dielectric Constant Transmission Electron Microscope