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The unique spontaneous polarization property and application of ferroelectric materials in photocatalysis

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Nano Research 2024年第5期17卷 3571-3585页

作者： Jinghua An Chang Xu Lu Li Bo Tang College of Chemistry Chemical Engineering and Materials ScienceKey Laboratory of Molecular and Nano ProbesMinistry of EducationCollaborative Innovation Center of Functionalized Probes for Chemical Imaging in University of ShandongInstitute of Molecular and Nano ScienceShandong Normal UniversityJinan 250014China Laoshan Laboratory 168 Wenhai Middle RdAoshanwei JimoQingdao 266237China

The unique spontaneous polarization property of ferroelectric material makes it to be a special catalyst in *** spontaneous polarization property can induce the formation of built-in electric field,which can improve the separation of photoelectrons and holes to affect photocatalytic *** internal electric field induced by spontaneous polarization can be influenced by multiple factors such as the morphology,the concentration of defect,the type of doped heteroatoms,as well as the composition of ***,the preparation method,pretreating temperature,the strength of prepolarized external electric field of ferroelectric-based photocatalysts as well as the strength of external mechanical force or external magnetic field in photocatalytic reactions can influence the photocatalytic effectivity via influencing spontaneous polarization-induced internal electric ***,it is urgently to unveil the mystery of structure-activity relationships for ferroelectric materials-based photocatalysts,which is usually *** this in mind,this review was provided for the role of various complex influencing factors on ferroelectric materials-based photocatalysis based on the latest advancement in the fields of new energy development,environmental *** the beginning,the basic structure and properties of ferroelectric material are ***,popular synthesis methods of ferroelectric-based photocatalysts are *** that,two main mechanisms of ferroelectric photocatalysis are *** research progress of ferroelectric photocatalysis is then given emphatically according to the classification of photocatalytic ***,the problems existing nowadays and the challenges facing in the future on the application of ferroelectric materials-based photocatalysts are outlined in the summary and outlook section.

关键词： spontaneous polarization photocatalysis ferroelectric separation of electrons and holes

Effectively improved piezoelectricity in high-temperature Arrhenius CBT ceramics by modifying potential energy profile and spontaneous polarization

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Journal of Advanced Ceramics 2024年第8期13卷 1143-1152页

作者： Jingwen Xi Linlin Liu Hongwei Qiao Jiacheng Luo Xin Su Xin Zhao Yugen Xu Hao Chen Zhi Tan Jianguo Zhu Nuclear Power Institution of China Chengdu 610213China College of Materials Science and Engineering Sichuan UniversityChengdu 610064China

Enhancing the piezoelectricity of CaBi_(4)Ti_(4)O_(15)(CBT)ceramics is crucial for improving their application potential in high-temperature piezoelectric ***,we propose a strategy involving the introduction of larger Na/Bi ions at the A-site,effectively inhibiting the tilt of oxygen octahedra and flattening the potential energy *** flattening enhances the variation in polarization under external ***,substituting Nb/Mn at the B-site increases the deviation between positive and negative ionic centers,leading to stronger spontaneous polarization,while the induced defect dipoles restrict oxygen vacancy migration and increase the direct current resistivity(ρ_(dc)).The flattened potential energy profile and increased spontaneous polarization significantly enhance the overall performance of cBT ceramics,with the piezoelectric constant(d_(33))reaching 25 pC/N when the Curie temperature(Tc)=752℃.Piezoresponse force microscopy(PFM)and transmission electron microscopy(TEM)revealed submicron-long rectangular domains and nanoscale domains in the modified composition,indicating a high density of domain *** study presents an effective approach for enhancing the piezoelectric properties of bismuth layered-structured ferroelectrics(BLSFs),thereby improving the application potential of BLSFsathightemperatures.

关键词： piezoelectricity bismuth layered-structured ferroelectrics(BLSFs) potential energy profile spontaneous polarization high temperatures

spontaneous polarization IN UNCONVENTIONAL Ta_(2)O_(5)DIELECTRIC CERAMICS BY LASER SINTERING

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Journal of Advanced Dielectrics 2011年第2期1卷 197-201页

作者： LINGFEI JI YIJIAN JIANG Institute of Laser Engineering Beijing University of Technology Beijing 100124P.R.China

spontaneous polarization was found in Ta_(2)O_(5)dielectric ceramics prepared by laser sintering *** heat corrosion,90°and 180°domains in the ceramics was observed by field emission scanning electron *** crystal structure of the laser-si ntered ceramics at RT was determined as monocinic phase,which indicates the lattice distortion existed in the *** variation of O-Ta-O bending vibration mode was deduced from the variation of phonon mode at the low wave-mumber(57 cm^(-1)and 250cm^(-1)).The enhancement of effective electric field for tantalum atoms due to the lattice distortion was determined by calculation of charge distribution *** distortion of crystal structure due to the phase transformation from higher symmetric orthorhombic phase to lower symmetric monoclinic phase expl ained spontaneous polarization in the laser-sintered Ta_(2)O_(5)ceramics.

关键词： spontaneous polarization tantalum-pentoxide domain dielectric ceramic

Critical behavior of the spontaneous polarization and the dielectric susceptibility close to the cubic-tetragonal transition in BaTiO_(3)

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Journal of Advanced Dielectrics 2015年第3期5卷 50-53页

作者： H.Yurtseven F.Oguz Department of Physics Faculty of Arts and Sciences Middle East Technical University06531 AnkaraTurkey Micro and Nanotechnology Program Graduate School of Natural Applied Sciences Middle East Technical University 06800 AnkaraTurkey

Using Landau mean field model,the spontaneous polarization and the dielectric susceptibility are analyzed as functions of temperature and pressure close to the cubic-tetragonal(ferroelectric-paraelectric)transition in BaTiO_(3).From the analysis of the dielectric susceptibility and the spontaneous polarization,the critical exponents are deduced in the classical and quantum limits for BaTiO_(3).From the critical behavior of the dielectric susceptibility,the spontaneous polarization can be described for the ferro-electric–paraelectric(cubic to tetragonal)transition between 4 and 8 GPa at constant temperatures of 0 to 200K in BaTiO_(3) within the Landau mean field model given here.

关键词： Dielectric susceptibility spontaneous polarization ferroelectric-paraelectric transition Landau mean field model BaTiO_(3)

Conductivity method of alkaline solution in evaluating the spontaneous polarization property of tourmaline

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Conductivity method of alkaline solution in evaluating the s...

High Curie Temperature, Large spontaneous polarization and Direct Band Gap in a Perovskite-like Molecular Ferroelectrics

2012 China Functional Materials Technology and Industry Forum

作者： Jun-ping Meng Jie liu Xiao-li Huo Juan Li Hebei University of technology Institute of Power Source and Ecomaterials Science

The spontaneous polarization property of mineral tourmaline was evaluated by the conductivity method of alkaline *** conductivity changing rate of the alkaline solution(k) was adopted as the evaluation *** this paper,the deionized water and alkaline solution were treated by mineral tourmaline powders,*** conductivity values were tested by a Digital Conductivity *** this basis,the conductivity difference was *** results showed that,the changing rate k increased as the spontaneous polarization *** 0spontaneous polarization was weak;when 2spontaneous polarization was stronger;when k>10,the spontaneous polarization was strongest.

关键词： Tourmaline spontaneous polarization Alkaline solution Conductivity Evaluation

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High Curie Temperature, Large Spontaneous Polarization and D...

Combined effect of the transition layer and interfacial coupling on the properties of ferroelectric bilayer film

2018年中西部地区无机化学化工学术研讨会

作者： Yun-Zhi Tang Chang-Feng Wang Chao Li School of Metallurgy and Chemical Engineering Jiangxi University of Science and Technology Ganzhou

Most of the molecular ferroelectrics suffer from the defects of low Curie temperature, small spontaneous and unitary performance, far away from the application in smart materials. [1-2] Here we reported a new perovskite-like molecular ferroelectrics [(γ-ammonium butyric acid)2 CdCl4]n, 1, which shows high curie temperature(355 K) and large spontaneous polarization(Ps = 7.2 u C/cm2). Especially, the further investigation shows that 1 is a direct-gap semiconductor with band gap(3.88 eV). X-ray single crystal diffractions measurement at 293 and 365 K reveals that the twist motions of γ-ammonium butyric acid and the relative "displacement" from positive ammonium and the negative [Cd(Ⅱ)Cl] triggered the para-ferroelectric phase transition. The exceptional dielectric response and heat anomalies as well as the X-ray diffraction powder diffraction dependence on temperatures further confirm its interesting reversible phase transition behaviour.

关键词： Molecular Ferroelectrics spontaneous polarization Direct Band Gap Pervoskite Structure

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Chinese Physics B 2009年第4期18卷 1658-1664页

作者：孙普男崔莲吕天全 Center of Condensed Matter Science and Technology Harbin Institute of Technology Physics Department Heilongjiang University

Within the framework of modified Ginzburg Landau-Devonshire phenomenological theory, a ferroelectric bilayer film with a transition layer within each constituent film and an interfacial coupling between two materials has been studied. Properties including the Curie temperature and the spontaneous polarization of a bilayer film composed of two equally thick ferroelectric constituent films are discussed. The results show that the combined effect of the transition layer and the interracial coupling plays an important role in explaining the interesting behaviour of ferroelectric multilayer structures consisting of two ferroelectrie materials.

关键词： ferroelectric bilayer film spontaneous polarization Curie temperature phase transition

Construction of spontaneously polarized ceramic via synergistic mechanical activation-Biomimetic mineralization for activating air and water

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Journal of Materials Science & Technology 2023年第34期165卷 132-142页

作者： Wuxiang Zhang Hongguang Zhang Ying Zhu Zuqiang Huang Yanjuan Zhang Tao Gan Huayu Hu Yuben Qin School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China Key Laboratory of New Low-carbon Green Chemical Technology Education Department of Guangxi Zhuang Autonomous RegionNanning 530004China

spontaneously polarized crystals with intrinsic electric dipole moment have attracted immense interest as excellent functional materials for extensive *** is of great significance to engineer sustainable spontaneously polarized materials with fascinating characteristics and performance for activating air and ***,a novel strategy based on the synergy of mechanical activation(MA)and biomimetic mineralization(BM)was created to construct spontaneously polarized *** induced the structural damage of clay and promoted the dissolution of ions and the release of free proteins,contributing to the formation of silicate precursor in BM *** high temperature firing,the silicate precursor in clay was converted to form KCa_(3)AlCa_(3)Si_(4)O_(16)(hexagonal crystal system,L^(6)symmetry type,and P63 space group)in the resulting spontaneously polarized *** non-centrosymmetric structure of KCa_(3)AlCa_(3)Si4O_(16)and the high intrinsic electric dipole moments contributed by K(1)polyhedrons resulted in high spontaneous polarization(0.2322μC/cm^(2))and far-infrared emissivity(0.951)of spontaneously polarized *** air,spontaneously polarized ceramic can activate H_(2)O and O_(2)molecules to form negative air ions owing to surface electric *** water,spontaneously polarized ceramic can disaggregate large water clusters to form small water clusters ascribed to surface electric field and far-infrared emission;water pH can be regulated from weak acidity to approximate neutrality via the capture of electrons by H+ions to produce releasable hydrogen *** work provides great promise for rational design and synthesis of spontaneously polarized materials for functional applications.

关键词： Ceramic spontaneous polarization Mechanical activation Biomimetic mineralization Activation of air and water

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