Abstract:This paper begins with the piezoelectric effect and introduces the classification and structure of piezoelectric materials.Considering the application of different piezoelectric materials in the production practice，preparative techniques of piezoelectric material in the current stage are listed。Research actuality of piezoelectric materials is summaried. application and development of the piezoelectric materials in various fields are also introduced systematically.

The (1-x)BiYbO3-xPbTiO3(x=0.95，0.90，0.85，BYPTx) ceramics were prepared by traditional solid state processing with solid metal oxides. XRD shown stable peroviskite phase with the solid solution limit is less than 15% (content of BY ). With the increasing of x, the tetragonality of BYPTx increased. BSYPTx ceramics showed the weak piezoelectric coefficient d33 were 23pC/N, and the Curie temperature of BYPTx ceramics was 583℃.

The uses of RHEED and MBE have been proved to be a powerful tool to understand growth mechanism and surface reconstruction of GaAs. This paper reported a new type method of molecular beam epitaxy. GaAs epilayer was grown on GaAs (001) substrate under the real-time monitoring of RHEED. By changing the growth and annealing time and temperature (480 ℃, 560 ℃, 610 ℃), combining the evolution of RHEED images with the relationship of GaAs surface roughness, a smooth GaAs surface at atomic scale has been obtained. After the growth, the sample was analyzed by EDS to show that the sample was high-purity GaAs, the thickness of GaAs epilayer was about 4μm.

GaSb thin films were grown on GaAs(001) substrates by Molecular Beam Epitaxy (MBE). The crystalline quality, electrical properties and optical properties were studied by high resolution transition electron microscopy (HRTEM), atomic force microscopy (AFM), Hall measurement and low temperature photoluminescence spectra (LTPL), respectively. It was found that the GaSb films directly grown on GaAs substrates have smooth surface and high hole mobility. It was also found that the AlSb/GaSb superlattices (SLs) can restrict the dislocations into GaSb layers. The intensity of PL spectra of GaSb layer became bigger homologous, which indicated that the optical qualities of GaSb films was improved.

By using sol-gel spin coating method nanostructured Pb(Zr0.53Ti0.47)O3 (PZT) ferroelectric thin films were fabricated on the Si substrates coated by nanoporous alumina membranes with average pore sizes of 20 - 100 nm, in which metal (Au or Pt) nanowires were embedded as a part of the bottom electrode. The dielectric, ferroelectric properties and microstructure of the nanostructured PZT thin films were characterized. The dielectric measurements demonstrated that the dielectric constant of the PZT nanofilms with a thickness of 25 nm decreased quickly from 860 to 100 as increasing the frequency below 104 Hz, and then remained almost constant of 100 as further increasing the frequency up to 106 Hz. Such a fast decrease of the dielectric constant in the low frequency region was resulted from the dielectric relaxation of space charges accumulated at the interfaces between the nanofilm and the (bottom and top) metal electrodes. The dielectric loss peak observed near 4000 Hz was contributed from the resonant absorption effect of the space charges. The polarization-electric field hysteresis loops of the nanostructured PZT films with a thickness 100 nm showed that the remanent polarization of the PZT nanofilm was 50 mC/cm2 and coercive field of 500 kV/cm. Cross-sectional TEM images showed that the nanostructured PZT films contacted directly with the bottom electrode (metal nanowires), and the interface between them exhibited some degree of waviness. It was found that some Au nanowires became into branches at their ends after post-annealing the PZT nanofilms, whereas such a phenomenon was effectively prohibited by using Pt nanowires. A selection of proper post-annealing temperature was the critical processing parameter for fabricating nanostructured PZT ferroelectric thin films as making a trade-off between the ordered metal nanowires within the anoporous alumina membranes and the crystallinity of ferroelectric nanofilms.

GaAs Curie temperature depends on carrier concentration and anti-ferromagnetic exchange interaction, This paper quantitatively analyzes the Influence of anti-ferromagnetic exchange interaction on the Curie temperature of p, n-type doped GaAs. Calculations prove that influence of anti-ferromagnetic exchange interaction on the Curie temperature of p, n-type doped GaAs is essentially different: p-type semiconductor materials, the Curie temperature is only with the anti-ferromagnetic exchange interaction, but with doping concentration has nothing to do; n-type semiconductor, the Curie temperature depends on the anti-ferromagnetic exchange interaction and doping concentration, and the high doping concentration the Curie temperature than low doping concentration is low.

Abstract： We prepared CNT-KNN (carbon nanotube and potassium sodium niobate) composite and studied its structure and properties. The result shows: (1) phase structure and microstructure of the CNT-KNN composites don’t change while the content of CNT varies; (2) 0.02wt‰ CNT addition can improve the d33, but addition>0.02wt‰ deteriorates d33; (3) dielectric constant and capacitance decrease in all composites and strongly depend on density of composite samples.

CdS nanoparticles were synthesized by using cadmium acetate, sodium sulfide and SBS-OH poyl(styrene-b-butadiene-b-styrene) as raw materials through salt-induced route in tetrahydrofuran-methanol-water. The optical properties and morphologies for the synthesized CdS nanoparticles were determined through UV-Vis and TEM measurements. The results show that stable corona-embedded CdS nanoparticles could be obtained by taking advantage of amphiphilic properties for SBS-HO micelles in tetrahydrofuran-methanol-water. UV-vis absorption and PL spectra show that CdS nanoparticles could give an apparent quantum confinement effects.

Based on the piezoeletric ceramic self-thoughening and considered the influence of the micro-cracks and pores ,a model of thoughness with grain size and distribution was built. The relationship among BaTiO3 piezoelectric ceramic toughenese , grain size and distribution were analyzed theoretically; Simultaneously, the effect of piezoelectric ceramic tougheness to coarse particles was analyzed. It’s shown that the simulation results is consistent with that of experiments.

Carbon nanotubes gas sensors are attracted more attentions for its exceptional properties of lower work temperature and detection limit. While the oxide semiconductor doping with carbon nanotubes gas sensors have the advantages both of carbon nanotubes gas sensors and oxide semiconductor gas sensors, such as higher sensitive, lower work temperature and detection limit. The progress and gas-sensing mechanism of this two kinds of gas sensors are introduced and summarized in this paper, and also the problems and developing tendency are pointed out.

This paper reports an experiment research which utilized of the molecular beam epitaxy technology to grow the InGaAs / GaAs film, the film growth conditions was monitored through the RHEED patterns in real-time, we measured the growth rate and determined the composition of In/Ga in InGaAs / GaAs film by RHEED intensity oscillations, and then put forward a method to control the composition of In/Ga in InGaAs / GaAs film. According to the RHEED patterns，the surface of InGaAs film was (2 × 3) reconstructed. After growth, the sample was quenched down and transferred into STM for scanning, a smooth, atomically flat surface of InGaAs / GaAs film was confirmed by the STM images.

The electromechanical properties of the piezoelectrets based on the irradiation cross-linked polypropylene (XPP) were investigated. The Young’s modulus of the XPP films were determined from the dielectric resonance spectra. The piezoelectric d33 coefficients in such piezoelectret films were measured by using quasi-static method. The thermal stability of d33 coefficients were investigated by isothermal annealing and thermally stimulated discharge. The time spectrum of piezoelectric response was analyzed. The experiments of the mechanical fatigues in the XPP piezoelectret films were also taken. The result shows that the Young’s modulus of the XPP films is around 1.3 MPa. The d33-coefficients exhibit good linearity in the range of applied pressure from 10 to 60 kPa. The d33 values decrease with the increase of the charging temperature. The time spectrum of piezoelectric response reveals a viscous flow feature in XPP films. The relation between the output voltage and applied force is linear. No significant change in d33 coefficients was observed after 600000 cycles of applying force.

A series of InxGa1-xAs films were grown on GaAs(001) substrates over the compositions range from InAs to GaAs(100%、39%、29%、19%、0%) by MBE. During the process of growing InxGa1-xAs, the growth rate and status was measured and monitored via RHEED oscillations and patterns respectively. Compared the RHEED oscillations and patterns, the growth mode turned rapidly from 2D to 3D with increasing of In composition. We draw a reasonable assumption to determine the composition of the InxGa1-xAs, and obtained ideal results. For the sample of composition of In0.19Ga0.81As, after growth and subsequent annealing, the STM images confirmed that the surface of this sample was atomically flat and (2×3) reconstructed.

A series Doppler broadening spectra of Bi4Ti3O12 and Bi3.25La0.75Ti3O12 ferroelectric films deposited on Silicon Substrate are measured by means of Variable-energy Positron Beam, the positron implantation energy dependence of shape parameter S are performed. The S(E) and W(E) data are analyzed dy plotting them in the S-W plane, the positron trapping states related to the structure of the samples are discussed. The results indicate that for the both samples the defects on the interface region between ferroelectric film and Si substrate are of multivacancy–Multioxygen complexes(VxOy) type. It also implys the doping of lanthanum is helpful to increase the diffusion resistance of the defects. Key Words: Variable-energy Positron Beam, Doppler broadening Spectrum,

A series of ferroelectric ceramics with variable compositions of (1-x)PZT-x(0.2PFN-0.2PZN-0.6PNN) (x=0.1, 0.2, 0.3, 0.4 0.5) were prepared by the precursor method. The proveskite structure and ferroelectric domains were studied by X-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. The morphotropic phase boundary was determined and the relations among electric property, composition and microstructure were briefly discussed. It was found from XRD data that with an increase of x value the crystal structures transformed from tetragonal to rhombohedral phase. The transformations from herringbone-like domain patterns with parallel stripes to small relaxor ferroelectric domains, observed by TEM, significantly influenced the electric properties. The Curie temperature decreased apparently with the increase of x values according to the temperature-dependent relative permittivity measurements. The typical feature of relaxor ferroelectrics was observed at x?0.3 with the maximum dielectric constants of 3050 at x=0.3. At x=0.2 the ceramics exhibited excellent dielectric, piezoelectric and ferroelectric properties: the maximal piezoelectric coefficient reached 485 pC/N with the maximal remnant polarization being 37μC/cm2. The maximal relative dielectric constant of 22000 was achieved at Curie temperature. The morphotropic phase boundary was determined to be 0.2<x<0.3 based on the experiment.

The cast iron surface is strengthened with the electrode of WC-8Co cemented alloy using electro-spark deposition (ESD) technique. The microstructure and properties of the coating were investigated by X-ray diffraction, scanning electron microscopy and Vickers hardness tester. The results show that ESD technique can produce dense coating on surface of the cast iron with proper process parameters. The coating consists of Fe3W3C, Co3W3C, Fe7W6 and W2C phases, and metallurgically bonded with the cast iron substrate. Nanometer-sized Fe7W6 and W2C particles dispersedly distribute in the coating. The maximum hardness of the coating is 1512.1 HV0.3, and its wear resistance is 2.3 times of the substrate. The wear mechanism includes abrasive and fatigue wear. Superfine hard phases which distribute dispersedly in coating are the main factors leading to high hardness and wear resistance of the coating.

The electrodeposition of cuprous oxides were investigated in an acid electrolyte, and the morphology and structure of Cu2O thin films electrodeposited by a two-electrode system Cu(II) solution were studied. The high bath temperature gave rise a faster reaction rate for Ac-HAc conjugated system, which prohibited the growth of metallic copper. The higher concentration of cupric ions was favor of the Cu2O growth through (200) plane due to a higher concentration gradient. The XRD results showed that Cu2O thin film can be electrodeposited over a large current domain (4 mAcm-2) as compared to those using a three-electrode system (1 mAcm-2). The Cu2O film has porous nature morphology with Eg of 2.4 eV.

0.55Pb(Ni1/3Nb2/3)O3–0.45Pb(Zr0.3Ti0.7)O3 (0.55PNN-0.45PZT) piezoelectric ceramics are high-performance piezoelectric materials, which are widely used to fabricate the fibers with Pt core and other electronic devices. In order to improve the electrical properties of the piezoelectric ceramic fibers, the 0.55PNN-0.45PZT ceramics with high electrical properties were fabricated by the traditional sintering method in this study. The effects of sintering temperature on the phase structure, microstructure and electrical properties of material have been investigated. High electrical properties ceramic were fabricated by optimizing the sintering temperature. The highest piezoelectric properties were observed when the ceramics were sintered at 1200℃ and their values were ρ=8.12g/cm3, d33=850pC/N, kp=0.62, εr=7317, tanδ=0.033, and Qm=41.66.

Abstract: (0.94-x)Bi0.5Na0.5TiO3–0.06BaTiO3–xLiNbO3 (BNBT–xLN, x=0–0.03) lead-free piezoelectric ceramics were prepared by solid state reaction method. The microstructure, ferroelectric, and piezoelectric properties of BNBT–xLN ceramics was investigated. The X-ray diffraction analysis shows that all of the ceramics have single-phase perovskite structure. The grain size becomes more identical and the density increases after the incorporation of certain amount of LiNbO3. For the ceramics with x ≤ 0.02, the remanent polarization (Pr) reduces slightly with increasing x. When x > 0.02, the polar and non-polar phases may coexist in the ceramics at room temperature, resulting in a sharp decline in the Pr and coercive field (Ec). With increasing x, both the dielectric constant (εr) and dielectric loss (tan?) increase gradually, and the piezoelectric constant (d33) increases initially and then decreases. The ceramics with x = 0.02 exhibit the optimum electrical properties: d33 = 150 pC/N, kp = 27%, Pr = 34.1 μC/cm2, Ec = 28.8 kV/cm. The depolarization temperature Td is shifted toward lower temperatures with increasing x.

The size 4mm of high-quality type Ⅱb large diamonds were synthesized by means of temperature-gradient-method under china cubic anvil apparatus which produces high temperature and high pressure. The impurities of nitrogen and boron in yellow, colorless and blue diamonds were measured by micro Fourier transform infrared (FTIR). The diamond which was synthesized by adding nitrogen getter and boron was concluded as a characterization of the type IIb diamond. In this paper, semiconductor properties of type Ⅱb large diamonds with the varied quantity of doped boron were detected by four-point probe and Hall effect method; The relationships of the quantity of doped boron and semiconductor properties of diamonds were summarized; The doped boron was played a key action in variation of semiconductor properties in type Ⅱb large diamonds.

The (K0.465+xNa0.465+yLi0.07)(Nb0.95-zSb0.05)O3 (with x, y, and z varying from -0.01 to 0.02) ceramics were prepared by conventional technique and the effect of nonstoichiometry on the phase transitions and piezoelectric properties of the ceramics were studied. The results reveal that the ceramics with stoichiometric composition have perovskite structure with tetragonal phase; the excess or deficiency of K or Nb component cannot change the symmetry of the ceramics in experimental composition range, however, the excess of Na component will lead to the increase of TO-T of the ceramics above room temperature and the TO-T increase with y in the range concerned; the volatilization loss of the alkaline K or Na can be compensated by adding ~0.5 % mol of K or Na content and enhanced piezoelectric properties are obtained; and the ceramics still have such promising piezoelectric properties d33>200 pC/N and kP>40% even with composition deviation from designed one (x =0~0.02 when y=z=0, y =0~0.01 when x=z=0, and z =-0.01~0.005 when x=y=0). These results are much favorable for the experimental work and/or for the mass production when the materials are adopted for devices applications.

Cellulose acetate film was prepared by solution casting method. Composite sensing film can be obtained via immobilization of fluorescent indicator and glucose oxidase on cellulose acetate film. Surface morphology of composite sensitive film and enzymatic activity were analyzed by scanning electron microscope and UV-visible spectrometer. Fluorescent indicator does not leak. The stability of the immobilized enzyme was higher than the free enzyme. All above indicate this kind of cellulose acetate film can be a good immobilization carrier of fluorescent indicator and enzyme.

Barium ferrite is prepared by high-temperature solid reaction process in this paper. The structure and morphology of the products are characterized by using X-ray diffraction (XRD) and scanning electronic microscope (SEM). The electrochemical properties of the barium ferrite electrodes are studied by using cyclic voltammetry and galvanostatic charge-discharge tests. The results show that for the second alkaline battery with BaFe2O4 as the positive material and hydrogen absorbing alloy as the negative material, it has good electrochemical activities and a stable discharge platform at above 1.2V. The reactant ratio has a great effect on the structure and electrochemical properties of the products and the optimal process is as follows: ratio between Fe2O3 and Ba(OH)2 1: 1.5, temperature 900 oC and reaction time 10 h.

Barium calcium titanate (Ba0.90Ca0.10)TiO3 ceramics were prepared by sol–gel technique. The evolution of the ferroelectric hysteresis loops was analyzed at frequencies ranging from 0.01 to 10 Hz and in a field of 1.5-20 kV/cm. The results show that the electric field and frequency dependence of hysteresis loops are obvious. At low field, coercive field (Ec) decreases monotonically with frequency increasing, and remanent polarization increases at low frequency. But at high field, Ec increases monotonically with frequency increasing, and the evolution of the hysteresis loops is not obvious with different testing frequency when the hysteresis loops become saturated.

Abstract：ZnS: Fe nanocrystals were synthesized in W/O micro-emulsions by using Span 80/Tween 80/cyclohexane/water systems. The crystalline, microscopy and luminescent properties of ZnS:Cr nanocrystals were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and photoluminescence (PL) spectra. The results show that ZnS:Fe nanocrystals have cubic zinc blende crystal structure, and the size of these spherical particles is 3nm. From PL spectra of ZnS: Fe nanocrystals in micro-emulsion with different doping concentrations of Fe ion, the intensity of the emission peaks in ZnS: Fe(1%) nanocrystals was found the strongest, indicating that doping concentration has a great influence on the luminescence properties of ZnS substrate. In addition, the fluorescence decay curves of the ZnS: Fe nanocrystals were tested, and the calculated fluorescence lifetime of the ZnS: Fe nanocrystal was 3.07 ns.

TiO2 nanotube arrays were prepared by anode oxidation in organic electrolytes. There were different morphologies by the different oxidation time. Their photoelectrochemical activities were examined with different bias applied on the Ti/TiO2 electrode by photo current response. The highest photo current was indicated by the regular nanotube of 6h oxidation at the bias E=0.1V. The characteristic parameters for TiO2 nanotube arrays such as carrier density, flat potential, width of space charge layer and badgap bending were calculated by Mott-Schottky curve and the growth mechanism of TiO2 nanotube arrays was suggested: TiO2 nanotube arrays were prepared under the combined effect of oxidation reaction and dissolution reaction. The detailed dynamics information of TiO2 nanotube arrays electrode at the semiconductor/electrolyte interface were obtained by equivalent electrical circuit fitting to EIS spectra. The photoelectrocatalytic rate was highest at the bias potential of 0.1V. The extra bias potential can decrease the electron-transfer resistance and increase the separation efficiency of photogenerated electron-hole pairs. The redox reaction in Helmholtz layer was the rate limiting step for the photoelectron- catalytic process of ammonia degradation.

Lead-free piezoelectric ceramics Li0.06(Na0.5K0.5)0.94NbO3+0.8mol%CuO (LNKN-Cu0.8) were synthesized by a traditional solid-phase sintering. The crystalline phase, microstructure and electrical properties of the ceramics were investigated with a special emphasis on the influence of sintering temperature. The density possesses a peak with increasing sintering temperature and reaches its peak value of 95% at 1020 oC. The X-ray diffraction analysis indicates that all ceramics possess a single perovskite structure without any other secondary phases over the whole sintering temperature range. Although MPB separating the orthorhombic and tetragonal symmetries was absent, the maximum piezoelectric coefficient (d33) of 196 pC/N was obtained at 1020 oC owing to the combined action of density and fine microstructure.

Piezoelectric ceramic can transfer mechanical energy around projectile launch environment into electrical energy. A new model building method is proposed to study the electric generating characteristic of piezoelectric power supply. The method includes two steps: first, deduce the formulas of output voltage, electric charge and electric energy of parallel connected piezoelectric stack through total energy partial differentiation method; second, transform the generating model of piezoelectric structure to equivalent circuit, and the final electric energy output expressions can be obtained through electricity analysis. Then utilize MATLAB to proceed numerical analysis for the new model of piezoelectric generation, finally a piezoelectric power supply is designed to optimize its electric energy production with the theoretical model.

A new lead-free piezoelectric ceramics of (Na0.84K0.16)0.5Bi0.5TiO3 was prepared by conventional solid state reaction, The influence of Sb3+ doping on microstmcture and properties of the lead free piezoelectric ceramics was investigated. The results show that the sample density reaches maximum version 5.85g/cm3 sintered at 1160℃, all compositions are of pure perovskite structure solid state, Sb2O3 doping changes crystal cell dimension and produces Bi+3 or Na + vacancy and without impurity phase; Doping in 0.4%~0.6%, dielectric constant first increases, then decreases, dielectric loss present increasing trend; doping 0.5% Sb2O3, d33 appears maximum 142pC/N.

(Na0.66K0.34)NbO3 ceramics were prepared by conventional oxide solid-solution technique and the effect of CuO on the piezoelectric, dielectric and ferroelectric properties were investigated. The experimental results showed that the doping of CuO facilitated the grain growth and lowered the sintering temperature. By proper doping of 0.5 mol% CuO, the sample density and mechanical quality factor Qm was improved to 4.26 g/cm3 and 400, respectively, the dielectric loss was depressed sharply from about 4.3% to 0.8%. The experimental results also showed that the doping of CuO has a “hard” effect on the properties of (Na0.66K0.34)NbO3 ceramics. The Curie temperature (TC), orthorhombic-tetragonal phase transition temperature (TT-O), piezoelectric coefficient d33 and electromechanical coupling coefficient kp decreased, whereas the coercive field Ec increased with increasing CuO content. The good property of d33=107 pC/N for the sample without CuO suggests that the composition of (Na0.66K0.34)NbO3 is another promising lead-free candidate for investigation besides (Na0.5K0.5)NbO3 system.

P(DHCA-co-LCA)-b-PEG polyesters were synthesized by polycondensation of 3,4-dihydroxycinnamic acid (DHCA, caffeic acid), lithocholic acid (LCA) and poly(ethylene glycol) (PEG). The structure and molecular weight of the P(DHCA-co-LCA)-b-PEG polyesters were characterized by fourier transform infrared (FTIR), nuclear magnetic resonance (1H-NMR) and gel permeation chromatography (GPC). The thermal and photosensitive properties of the polyesters were investigated by differential scanning calorimeter (DSC), UV spectroscopy and fluorescence spectroscopy. It is proved that glass transition temperature (Tg) and fluorescence emission intensity of the polyesters decreased when PEG increased in feed, but the fluorescence emission intensity of the polyesters obviously higher than DHCA monomer. P(DHCA-co-LCA)-b-PEG polyesters could be photo-crosslinked under λ>310nm UV light and its reversible photo-cleavage could take place under UV light of 254nm. The micelle nanoparticles were obtained by self-assembly at selective solvent. It was found that these nanoparticles have a nice spherical morphology with a smooth surface and possessed a certain photosensitivity based on the analysis of laser light scattering (LLS) and transmission electron microscopy (TEM). Their average diameter was about 378nm.

this paper analyzes ,when Mn and Cr co-doped, anti-ferromagnetic exchange interaction makes the Curie temperature of material decrease; in order to prepare high Curie temperature of the material requires higher doping concentration , preparation of high Curie temperature of the material more difficult; a high hole concentration can effectively suppress anti-ferromagnetic exchange interaction in the Curie temperature of the material.

ABSTRACT: By pulsed laser deposition(PLD), Hf0.2Zr0.8O2（HZO）thin films were fabricated on Pt/Ti/SiO2/Si substrates under different temperatures and oxygen pressures respectively. The impact of the technical conditions on the films’ structural and ferroelectric properties was studied. The films were characterized by X-ray diffraction (XRD) and Radiant RT66A. The results figured that, the ferroelectric polarization was resulted from the impact of the orthorhombic phase HfO2-ZrO2(111) and tetragonal phase ZrO2（002）. 18Pa, 500℃ were the optimized parameters of the Hf0.2Zr0.8O2 films on Pt/Ti/SiO2/Si. On the optimized condition ,the film’s 2Pr was 4μC/cm2.

The modified 1-3 piezocomposites were prepared in order to improve the stability of underwater acoustic transducers. The composite consists of 1-3 ceramic/epoxy composite and ceramic plate with series pattern. The cylinder transducer array made of modified 1-3 composite was fabricated. The performance of the transducer was investigated. The resonance frequency is 72kHz when the diameter of the transducer is 85mm. The transmitting voltage response reached 139dB at 72kHz, the receiving sensitivity was -212±4dB in the frequency range of 20kHz to 60kHz, the directivity response was even in horizontal direction and the beam width was 12° in vertical direction.

Polycrystal ceramics of Pb(Zr0.52Ti0.48)O3 with tetragonal phase and average sizes of uniformly distributed grains being 2～3μm were prepared through a conventional solid state route. In-situ Raman measurements on individual single grain and multiple single grains in subsequence were carried out under a stress field by employing a four-point bending load. The relative intensity ratios of optical modes at lower Raman shifts (IE(1LO)/IE(2TO) and IE+B1/IE(2TO)) under different applied stresses were calculated by normalizing peak intensity. The results revealed that the values of (IE(1LO)/IE(2TO) and IE+B1/IE(2TO)) decreased with the increases in the applied tensile or compressive stresses, while increased with the extension of applying time. The values of (IE(1LO)/IE(2TO) and IE+B1/IE(2TO)) varied with the alterations of applied stresses on different single grains. However, the peak position of Raman spectra remained unchanged.

(Pb,La) (Zr,Ti) O3 antiferroelectric thick film which had high (100) orientation, smooth surface and dense structure was prepared on Pt(111)/Ti/SiO2/Si substrate by sol-gel technology. The electrical properties of (Pb,La) (Zr,Ti) O3 antiferroelectric thick film under various temperature and dc electric fields were studied. The experimental results show that: antiferroelectric thick film happened mutual phase transformation of antiferroelectric, ferroelectric and paraelectric depending on temperature and electric field. The phase transition temperature of antiferroelectric - ferroelectric gradually decreases with the increase of applied electric field. The peak value of dielectric constant decreased from 2410 to 662. The phase transition current density increased from 2.21 × 10-7A/cm2 to 8.52 × 10-7A/cm2. The phase transition electric field of antiferroelectric–ferroelectric gradually decreases with the increase of applied temperature field. The relevant saturation polarization changed from 39uC/cm2 to 31uC/cm2. The phase transition current density decreased from 2.89 × 10-5 A/cm2 to 8.8 × 10-6A/cm2. The phase transition current characterization can be effectively adjusted by coupling application of temperature field and dc electric field.

An alkali-soluble photosensitive prepolymer was synthesized as photoresist by one-step process. hydroxyethyl acrylate was reacted with phthalic anhydride at different molar ratios, the influences of synthetic process, such as the reaction time, the concentration of catalyst and feeding method were discussed in details. By using a suitable photoinitiator, this resin was polymerized in the exposure of UV light, a series properties of cured film were investigated. For example, it can stand 10% hydrochloric acid for over 30 minutes and be striped in 1% NaOH within 2 minutes.

The ternary compound ferroelectric thin films, 6% Pb(Mn1/3, Nb2/3)O3- 94%Pb（Zr0.45, Ti0.55）O3(PMnN-PZT), are deposited on the MgO substrates by the magnetron sputtering method, and the quench method is adopted for the post heat treatment. The out-plane and in-plane X-ray diffractions are used to characterize the crystal structure of the PMnN-PZT thin films, and the highly accurate scan electron microscope is used to observe the surface and the cross section surface of the thin films. It can be obtained that the PMnN-PZT thin films own single crystal structure and perovskite phase.

Abstract: xPbTi0.4716Zr0.4834(Mn1/3Sb2/3)0.0450O3-(1-x)(K0.485Na0.485Li0.03)NbO3 [xPMS-(1-x)KNLN] ceramics with low-lead Component were prepared by using conventional ceramics method. Microstructure, piezoelectric and ferroelectric properties of the low-lead ceramics with different stoichiometry x fabricated at varied sintering temperature were studied. The XRD patterns of the ceramics show that the microstructure of the ceramics transform from a coexistence state of pyrochlore and pseudo-cubic pervoskite to tetragonal pervoskite while sintering temperature increases. The SEM analysis shows that a liquid-phase formed by the (K0.485Na0.485Li0.03)NbO3 component appeared during the sintering process and while the sintering temperature increases the holes appeared on the surface of the ceramics and disappeared when the ceramics were sintered at even higher sintering temperature. The electric measurement results obtained show that xPMS-(1-x)KNLN ceramics possess good piezoelectric and ferroelectric properties, and when sintered at 1250 ℃, the xPMS-(1-x)KNLN ceramics with x=0.75 ceramic possess the properties of d33=182 pC/N， kp=34.5 %， Tc=165 ℃， Pr=21.2 μC/cm2， Ec=1.47 kV/mm, εr=1879， and tanδ=0.92%.

Abstract: The (Ba0.9Ca0.1)(Zr0.15Ti0.85)O3 powders have been successfully prepared by sol-gel method, and the BCT-BZT lead free piezoelectric ceramics were obtained by traditional two-step sintering method under lower temperature(1290℃). The reaction process was analyzed with the help of the thermo gravimetric and differential scanning calorimetry. X-ray diffraction results showed that the structure of the BCT-BZT powders and ceramics were typical perovskite structure and the particle size was approximately 32 nm by Scherrer calculation. Moreover, the dielectric constant of ceramic was 6134 at the room temperature by TF analyzer 2000; the Curie Temperature was about 95℃. Especially, the piezoelectric response loops revealed that the maximum piezoelectric coefficient d33 reached 263 pm/V. We successfully get BCT-BZT lead-free piezoelectric ceramics by the method, the sintering temperature was about 200℃ lower than the solid phase reaction method, maintaining the good piezoelectric properties and reducing the sintering costs. So, it is conducive to realizing the large-scale industrial production of ceramics.