Relevant bibliographies by topics / Lead zirconate titanate ; Thin films – Electric properties

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  1. Journal articles
  2. Dissertations / Theses
  3. Conference papers

Academic literature on the topic 'Lead zirconate titanate ; Thin films – Electric properties'

Author: Grafiati
Published: 4 June 2021
Last updated: 17 February 2022

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Journal articles on the topic "Lead zirconate titanate ; Thin films – Electric properties"

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Cornelius, Thomas W., Cristian Mocuta, Stéphanie Escoubas, et al. "Piezoelectric Properties of Pb1−xLax(Zr0.52Ti0.48)1−x/4O3 Thin Films Studied by In Situ X-ray Diffraction." Materials 13, no. 15 (2020): 3338. http://dx.doi.org/10.3390/ma13153338.

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The piezoelectric properties of lanthanum-modified lead zirconate titanate Pb1−xLax(Zr0.52Ti0.48)1−x/4O3 thin films, with x = 0, 3 and 12 mol% La, were studied by in situ synchrotron X-ray diffraction under direct (DC) and alternating (AC) electric fields, with AC frequencies covering more than four orders of magnitude. The Bragg reflections for thin films with low lanthanum concentration exhibit a double-peak structure, indicating two contributions, whereas thin films with 12% La possess a well-defined Bragg peak with a single component. In addition, built-in electric fields are revealed for low La concentrations, while they are absent for thin films with 12% of La. For static and low frequency AC electric fields, all lanthanum-modified lead zirconate titanate thin films exhibit butterfly loops, whereas linear piezoelectric behavior is found for AC frequencies larger than 1 Hz.
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Sidorkin, A. S., S. D. Milovidova, O. V. Rogazinskaya, E. V. Ionova, A. B. Plaksitsky, and S. A. Bavykin. "Pyroelectric Properties of Lead Zirconate-Titanate Thin Films." Ferroelectrics 397, no. 1 (2010): 108–11. http://dx.doi.org/10.1080/00150193.2010.484743.

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Kartawidjaja, Fransiska Cecilia, Zhaohui Zhou, and John Wang. "Ferroelectric properties of heterolayered lead zirconate titanate thin films." Journal of Electroceramics 16, no. 4 (2006): 425–30. http://dx.doi.org/10.1007/s10832-006-9892-2.

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Lee, Sung Gap, Sang Man Park, Young Hie Lee, and Sung Pill Nam. "Dielectric Properties of Sol Infiltrated Lead Zirconate Titanate Ferroelectric Thick Films." Materials Science Forum 544-545 (May 2007): 549–52. http://dx.doi.org/10.4028/www.scientific.net/msf.544-545.549.

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Ferroelectric PZT(70/30) thick films were fabricated by the hybrid technique adding the sol coating process to the screen-printing process to obtain a good densification. Structural and electrical properties of the thick films with the sol concentration were investigated. The relative dielectric constant increased and dielectric loss decreased with increasing the sol concentration, the values of the thick film coated with sol concentration of 1.5 M were 698 and 2.5 % at 1 kHz, respectively. And the remanent polarization and dielectric breakdown strength of the thick film coated with sol concentration of 1.5 M were about 38 μC/cm2 and 200 kV/cm, respectively. The leakage current densities were less than 10-8 A/cm2 at the applied electric field range of 0-100 kV/cm in all thick films.
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Boyle, Timothy J., Paul G. Clem, Bruce A. Tuttle, et al. "Lanthanide series doping effects in lead zirconate titanate (PLnZT) thin films." Journal of Materials Research 17, no. 4 (2002): 871–78. http://dx.doi.org/10.1557/jmr.2002.0126.

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Lanthanide (Ln) doping of lead zirconate titanate (PLnZT 4/30/70) thin films was conducted to investigate effects on structural and electrical properties. Films were spin-coat deposited from precursor solutions made using a previously reported “basic route to PZT” chemistry. The remanent polarization (Pr), dielectric constant (ε), dielectric loss (tan δ), and lattice parameter values were obtained for each of the doped PLnZT films. Films doped with amphoteric cations (Tb, Dy, Y, and Ho) displayed high Pr values, square hysteresis loops, and enhanced fatigue resistance. Smaller radius Ln-doped films display an increased tendency toward (100) orientation in otherwise (111)-oriented films.
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Zhu, Derui, Qiujun Li, Tianshu Lai, Dang Mo, Yuhuan Xu, and J. D. Mackenzie. "Optical properties of lead lanthanum zirconate titanate amorphous thin films." Thin Solid Films 313-314 (February 1998): 210–13. http://dx.doi.org/10.1016/s0040-6090(97)00819-5.

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Gaskey, C. J., K. R. Udayakumar, H. D. Chen, and I. E. Cross. "“Square” hysteresis loops in phase-switching Nb-doped lead zirconate stannate titanate thin films." Journal of Materials Research 10, no. 11 (1995): 2764–69. http://dx.doi.org/10.1557/jmr.1995.2764.

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Niobium-doped lead zirconate stannate titanate thin films have been prepared by a modified sol-gel spin on technique, utilizing the hydrolysis-resistant precursor lead acetylacetonate. Films of compositions in the antiferroelectric tetragonal and antiferroelectric orthorhombic phases were prepared and phase-switched with the application of appropriate electric fields. A distinctly “square” hysteresis response was observed in a low titanium, low tin, orthorhombic composition, with a maximum polarization, Pmax, of 40 μC/cm2 and switching field values of Ef = 175 kV/cm and Ea = 75 kV/cm, while varying degrees of squareness, along with lower polarizations and switching fields, were observed in the higher tin, tetragonal compositions. Electric field-induced strains of up to 0.33% have been measured in the orthorhombic composition, with tunable electromechanical coefficients. Film properties showed only slight variation with electrode size over a range of diameters from 0.8 mm to 6.35 mm; large area electrodes are vital for practical actuator and sensor devices. With a capacitance density of 30–35 μF/cm2, films of the orthorhombic composition are promising as power plane decoupling capacitors in multichip modules.
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Yu, Shuhui, Kui Yao, Santiranjan Shannigrahi, and Francis Tay Eng Hock. "Effects of poly(ethylene glycol) additive molecular weight on the microstructure and properties of sol-gel-derived lead zirconate titanate thin films." Journal of Materials Research 18, no. 3 (2003): 737–41. http://dx.doi.org/10.1557/jmr.2003.0100.

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Poly(ethylene glycol) (PEG) additives with different molecular weights were used to modify sol-gel precursor solutions for preparing lead zirconate titanate (PZT) thin films. The morphology, crystalline structure, and mechanical and electrical properties of the films were characterized. The relationship between the characteristics of the films and the molecular weight of PEG was investigated. It was observed that the PEG eliminated cracking of the films during multiple pyrolysis treatments. However, with the increase of the PEG molecular weight, the films became less dense, which led to decreased Young's modulus and dielectric constant and increased coercive field. Our experiments showed that films prepared from sols modified by PEG with a molecular weight of 200 exhibited a dense morphology and excellent mechanical and electric properties without cracking.
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Griswold, E. M., M. Sayer, D. T. Amm, and I. D. Calder. "The influence of niobium-doping on lead zirconate titanate ferroelectric thin films." Canadian Journal of Physics 69, no. 3-4 (1991): 260–64. http://dx.doi.org/10.1139/p91-043.

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Ferroelectric thin films have recently proven viable for nonvolatile memory applications in semiconductor technology. Current research is focused on the development of processing technologies and deposition on metallized semiconductor substrates. In this study, niobium-doped lead zirconate titanate thin films were prepared by a dc magnetron-sputtering technique using a multielement metal target. Films were deposited on indium tin oxide coated glass and on metallizations on silicon substrates. The crystallographic structure and surface morphology of the films was examined by scanning electron microscopy and X-ray diffraction as a function of processing variables such as sputtering pressure, film thickness, and niobium content. Electrical characterization of the films is discussed in terms of ferroelectric hysteresis and polarization properties. Improved ferroelectric properties are achieved through a densified structure resulting from niobium-doping.
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Tanase, Tomokazu, Yoshio Kobayashi, Toshihide Nabatame, Takao Miwa, and Mikio Konno. "Dielectric properties of lead zirconate titanate thin films seeded with barium strontium titanate nanoparticles." Thin Solid Films 471, no. 1-2 (2005): 71–75. http://dx.doi.org/10.1016/j.tsf.2004.04.048.

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Dissertations / Theses on the topic "Lead zirconate titanate ; Thin films – Electric properties"

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Garcia, Melendrez Jose Angel. "Ferroelectric and ferroelastic phenomena in PZT thin films." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.707904.

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Tong, Sheng. "Dielectric and Ferroelectric Properties of Lead Lanthanum Zirconate Titanate Thin Films for Capacitive Energy Storage." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1352993943.

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Chen, Yu-Cheng, and 陳昱丞. "Heterolayered lead zirconate titanate / platinum thin films and the electric properties." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/01861463759065520138.

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Juan, Pi-chun, and 阮弼群. "The Electrical Properties of Lead Zirconate Titanate Ferroelectric Thin Films for Dielectric Applications in Non-Volatile Memory Devices." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/f526uc.

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博士<br>國立清華大學<br>電機工程學系<br>94<br>Abstract Lead zirconate titanate Pb(Zr0.53,Ti0.47)O3 (PZT) is a promising ferroelectric material for VLSI circuit applications especially in ferroelectric random access memories (FRAM) and DRAM. Its large dielectric constant and rapid switching characteristics can meet the requirements for both storage devices. However, before PZT films can be fully utilized, its electric properties need to be better understood. MFIS structure have emerged as promising non-volatile memory devices. The superior characteristics of MFIS include a single-device structure, low power consumption and non-destructive read-out operation. In this thesis, metal/PZT/metal capacitors, metal/PZT/insulator/silicon capacitors and metal/PZT/insulator/silicon transistors were fabricated. The temperature dependence of the current conduction mechanisms in Au/PZT/Pt metal-insulator-metal (MIM) thin film capacitors was investigated. The dominant current conduction mechanism from 300K to 375K is space-charge-limited current (SCLC) due to holes and changes to Schottky emission in the temperature range of 400K-500K. The transition voltage (Vtr) of SCLC conduction and the trap-filled-limited voltage (VTFL) were measured. The deep trap level extracted from VTFL is positioned at 0.39 eV above the valance band edge. The Au/PZT barrier height extracted from Schottky emission is 0.85 eV. The electrical conduction currents through the MIM capacitors depend on the electrode material due to different work functions of the metal electrodes. The conduction current observed in Au/PZT/Pt is lower by about two orders of magnitude compared to that of Pt/PZT/Pt at low field (<0.4 MV/cm) due to the larger barrier height for holes of Au/PZT. The energy band diagrams of the Au/PZT/Pt and Pt/PZT/Pt structures are compared. Hole transport is used to explain the conduction mechanisms in these two capacitor structures. MFIS capacitors with PZT ferroelectric layer and HfO2, La2O3 and Dy2O3 insulator layers were fabricated. The purpose of the insulator layer is to prevent the reaction and inter-diffusion between the ferroelectric layer and silicon substrate as well to improve the retention properties. The size of the capacitance-voltage (C-V) memory windows was investigated. The temperature dependence of the current conduction mechanisms through the MFIS capacitors was also investigated. The oxide trapped charges in the ferroelectric/insulator layers are studied by a voltage stress method. The flatband voltage (VFB) is measured before and after the voltage stress. The energy band diagram of the MFIS structure at inversion and accumulation modes are plotted and the VFB shift can be explained by the trapping or de-trapping of charges. The result is consistent with the charge trapping model. Metal-Ferroelectric-insulator-semiconductor (MFIS) field effect transistors with PZT ferroelectric layer and lanthanide oxide Dy2O3 insulator layer were fabricated. The memory windows measured from C-V curves of MFIS capacitors and IDS-VGS curves of MFIS transistors are consistent. The non-volatile operation of MFIS transistors was demonstrated by applying positive/negative writing pulses. A high driving current of 9 mA/mm was obtained even for long channel devices with a channel length of 20 mm. The electron mobility is 181 cm2/V-s. The retention properties of MFIS transistors was also measured.
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Chou, Hung-Che, and 周宏哲. "The temperature dependent electrical properties of lead zirconate titanate Pb(Zr0.53Ti0.47)O3 thin film capacitors." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/81990326267603020341.

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碩士<br>國立清華大學<br>電子工程研究所<br>91<br>Au/PZT/Pt and Pt/PZT/Pt metal-insulator-metal(MIM) thin film capacitors are prepared by radio-frequency sputtering. Below 375K, the conduction current is found to be Ohmic at low field and space-charge-limited current (SCLC) at high field. At high temperatures (>375K), the conduction mechanism becomes Schottky emission at field between 0.2 and 0.8 MV/cm. Using Ohmic conduction, EF-EV = 0.6 eV and μ=2.93×10-6 cm2/V-sec are calculated. Et-EF = 0.09 eV and Nt=2.8×1018 cm-3 are obtained from SCLC effect. Au/PZT barrier height 0.89 eV is extracted by Schottky emission. Au/PZT/Pt band diagram is proposed. The conduction current of Pt/PZT/Pt is found to be Ohmic conduction at low field and Poole-Frankel emission at high field.
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Graham, Joseph Turner. "A study of the ferroelectric properties of neutron irradiated lead zirconate titanate." 2013. http://hdl.handle.net/2152/21407.

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Lead zirconate titantate (PZT) is an electroceramic material with many important technological applications in sensing and computer memory. Some of these applications require the PZT based devices to operate in radiation fields where they will be exposed to a high flux of energetic, heavy and light, charged and uncharged particles. The risk to any device exposed to ionizing radiation is the accumulation of displacement and ionization damage. Significant damage accumulation over time can lead to property drifts and, in some cases, failure of the device to perform properly. The goal of the undertaking recounted in this dissertation was to study changes in the ferroelectric properties of PZT exposed to the neutron field of a research nuclear reactor and to help develop an understanding for the type of radiation induced defects that play a dominant role in the degradation process. Thin film PZT capacitors were prepared using a wet chemical technique. The capacitors were then irradiated in a 1 MW TRIGA research nuclear reactor at the University of Texas at Austin up to a maximum 1 MeV equivalent neutron flux of 5.2 x 10¹⁵ cm⁻². Following irradiation, electronic characterization of polarization-electric field hysteresis loops, first order reversal curves, and small-signal permittivity were performed to ascertain tendencies between irradiation dose and ferroelectric properties. The measurements indicate a drop in remanent polarization, a loss of domain wall mobility, shifts in local switching fields and the formation of dipolar defects. These effects are all attributed to the introduction of defects into the material through displacement damage cascades. Numerical models of the damage cascades were performed to determine the displacement concentration. Comparison of those values and the primary recoil spectrum with typical survival rates found in the literature suggest that both free point defects as well as defect clusters are produced in comparable if not larger concentrations. It is proposed that defect clusters play a more significant role in ferroelectric property change than previously believed.<br>text
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Chen, Jimmy, and 陳世明. "The temperature dependent electrical properties of led zirconate titanate Pb(Zr0.53,Ti0.47)O3 thin film capacitors." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/78469715193266127746.

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Chen, Meng-cheng, and 陳盟盛. "Material properties of the lead zirconate titanate thin films prepared using sol-gel and induction annealing." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/44857722444941550851.

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碩士<br>國立高雄第一科技大學<br>機械與自動化工程研究所<br>99<br>The study investigates the material properties of the lead zirconate titanate thin films prepared using sol-gel and induction annealing. The material characteristics of the piezoelectric thin films annealed using two heat treatment methods, furnace heating and induction heating, are compared. The parameter design using Taguchi method suggests an optimum poling condition at the double coercive electric field for one minute at 25ºC. The capacitance enhances from 4.21 to 4.62 (nF), the relative dielectric constant (εr) from 352 to 390, and the remanent polarization from 28.4 to 31.3 (μC/cm2). The coercive field also largely decreases from 237.5 to 186.9( kV/cm). The transverse piezoelectric strain constant (d31) and the longitudinal piezoelectric strain constant (d33) improve 22%. Meanwhile, this study explores the feasibility of the application of induction annealing during the preparation of PZT thin film. Heat the graphite thin plate under the wafer with induction coil so that the PTZ thin film could be heated through the heat conduction. Preliminary results shows the piezoelectric thin film can be successfully crystallized with a remanent polarization of 20.1(μC/cm2) and coercive field of 225.7(kV/cm). Eventually, the PZT thin film is introduced to the fabrication of inertial vibration device. The sensitivity is 6.65x10-3 (pC/g) at the frequency of 3,000 Hz.
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Conference papers on the topic "Lead zirconate titanate ; Thin films – Electric properties"

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Che, Lingjuan, Jinrong Cheng, Shengwen Yu, Chao Chen, and Zhongyan Meng. "Electrical Properties of Lead Zirconate Titanate Thin Films by a Hydrothermal Method." In 15th IEEE International Symposium on Applications of Ferroelectrics. ISAF 2006. IEEE, 2006. http://dx.doi.org/10.1109/isaf.2006.4387889.

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Zheng, Ping, Jinrong Cheng, Wei Lu, and Zhongyan Meng. "Thickness-dependent electrical properties of lead zirconate titanate thin films on titanium substrates." In SPIE Proceedings, edited by Junhao Chu, Zongsheng Lai, Lianwei Wang, and Shaohui Xu. SPIE, 2004. http://dx.doi.org/10.1117/12.607622.

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Ho, Kuan-Ting, Daniel Monteiro Diniz Reis, and Karla Hiller. "Defects and Resistance Degradation of Sputtered Doped Lead Zirconate Titanate Thin Films." In 2021 IEEE International Conference on the Properties and Applications of Dielectric Materials (ICPADM). IEEE, 2021. http://dx.doi.org/10.1109/icpadm49635.2021.9493888.

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Shin, Minchul, Jongsoo Choi, Ryan Q. Rudy, et al. "Micro-Robotic Actuation Units Based on Thin-Film Piezoelectric and High-Aspect Ratio Polymer Structures." In ASME 2014 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/detc2014-35145.

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A fabrication procedure is presented for creating microactuation elements that link piezoelectric thin-films with high-aspect ratio parylene microstructures. Resulting actuators permit relatively large rotational motions for low voltage operation, while maintaining large weight-bearing capacity. Actuator fabrication is performed on a silicon wafer though a combination of metal and thin-film lead-zirconate-titanate (PZT) deposition and patterning, parylene refill of high-aspect ratio trenches, and dry release of moving parts from the silicon substrate. Static and dynamic responses of various test structures are measured, to estimate material properties of the integrated PZT-polymer structures, for use in future actuator modeling and optimization.
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Lee, Cheng-Chun, G. Z. Cao, and I. Y. Shen. "Actuation Enhancement of PZT Thin-Film Membrane Actuators via Stress Relief Grooves." In ASME 2008 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/detc2008-49283.

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Lead Zirconate Titanate Oxide (PbZrxTi1−xO3 or PZT) is a piezoelectric material widely used as sensors and actuators. For microactuators, PZT often appears in the form of thin films to maintain proper aspect ratios. A common design is PZT membrane microactuator, whose actuation portion takes a form of a thin diaphragm driven by a PZT thin film. To maximize actuation displacements, finite element analyses are conducted to identify critical design parameters of the PZT film. In the simulation, a constant driving electric field is maintained and boundary conditions of the PZT film are varied. The finite element analyses lead to two important results. First, the actuator displacement increases as the PZT film thickness increases, but saturates at a critical PZT film thickness. Second, when stress relief grooves are introduced and the PZT film surrounding the membrane area is removed, the actuator displacement increases substantially by at least a factor of 5.
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Tang, Haixiong, Henry A. Sodano, and Yirong Lin. "Enhanced Energy Storage in Nanocomposites Through Aligned PZT Nanowires." In ASME 2011 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. ASMEDC, 2011. http://dx.doi.org/10.1115/smasis2011-5141.

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Nanocomposites consisting of a piezoceramic inclusion and polymer matrix offer a combination of electromechanical coupling with high toughness and ductility inherent to polymers. There is a wide range of applications for these types of materials due to their intrinsic piezoelectric and dielectric properties, such as vibration sensing, actuation, energy harvesting and capacitive energy storage. However, the relatively low piezoelectric strain coefficient and dielectric permittivity of these nanocomposites significantly limit their application in energy conversion and energy storage applications. There are mainly two coupled to improve the dielectric permittivity and electromechanical properties of piezoceramic nanocomposites, namely higher aspect ratio active inclusions and alignment of inclusions in the direction of the applied electric field. Previously, we have demonstrated that using higher aspect ratio lead zirconate titanate (PZT) nanowires (NWs) could significantly enhance the energy density and d33 coupling as compared to the samples with lower aspect ratio PZT nanorods [11]. In this paper, we will show that orientation of PZT NWs also influences energy storage capability of nanocomposite. Nanocomposites with aligned PZT NWs in the direction of the applied electric field show increased dielectric permittivity and energy density as compared to those with randomly dispersed inclusions. PZT NWs are hydrothermally synthesized, dispersed into a polyvinylidene fluoride (PVDF), cast into a film and then aligned through uniaxial stretching. Scanning electric microscopy (SEM) shows the PZT NWs are successfully aligned in direction of stretching. This work demonstrates that the energy storage and conversion capability of the nanocomposite can be significantly enhanced through the alignment of PZT NWs in the direction of the applied electric field. The findings of this research could lead to broad interest due to demonstration of developing piezoceramic nanocomposites with enhanced dielectric and electromechanical properties for next generation energy storage and conversion devices.
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Shieh, Jay, Szu-Wei Chen, and Chia-Yu Fang. "Photocurrent Response of Composite Perovskite Oxide Thin Films With Specific Semiconducting and Ferroelectric Properties." In ASME 2013 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/smasis2013-3058.

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The goal of this study is to investigate photocatalytic semiconductor systems which are layered thin film composites built from perovskite oxide materials with characteristics such as small and large band gaps and/or ferroelectricity. In order to improve the efficiency of photocatalysis, semiconductor heterojunctions within the developed composites have been designed to possess electronic band offsets favoring the separation of photo-induced electron and hole (e−/h+) pairs. Furthermore, the remanent polarization of the ferroelectric component within the composites has been utilized to induce favorable band bending at the material interface, lowering the potential barrier for electron transfer. The band offsets and ferroelectric polarization could be considered as built-in electric fields; how they interact with photo-induced e−/h+ would greatly affect the photocatalytic properties of the composites. In this study, various perovskite oxide thin film materials — large band gap strontium titanate (SrTiO3), small band gap silver niobate (AgNbO3) and ferroelectric lead lanthanum titanate (PLT) — were combined to form layered thin film composites. The composites were then adopted as photoanodes in a photoelectrochemical cell and detailed characterization of their photocurrent response was carried out under different light irradiation and ferroelectric polarization conditions. Electronic band offsets at the material interface (i.e., heterojunction) were determined by ultraviolet-visible spectrophotometry and ultraviolet photoelectron spectroscopy. Electric field poling of the ferroelectric component was achieved by non-contact corona charging. Our results have shown that the band offsets at the SrTiO3-AgNbO3 heterojunction were about 1.0 eV in conduction band edge and 0.4 eV in valence band edge, promoting the rapid separation of photo-induced charge carriers; i.e., the flow of e− from SrTiO3 to AgNbO3 and the flow of h+ from AgNbO3 to SrTiO3. It was found that ferroelectric PLT could be used as a seeding layer for the low-temperature (500 °C) growth of SrTiO3/AgNbO3 thin film composites on ITO/glass substrates, forming a layered structure of SrTiO3/AgNbO3/PLT/ITO. In addition, the photocurrent density of the composites could be increased by depositing gold nanoparticles at the PLT-ITO interface. When the polarization of the PLT layer was poled toward the AgNbO3 layer, the potential barrier associated with the flow of e− to the ITO electrode was reduced by favorable band bending created at the AgNbO3-PLT interface. This resulted in a significant increase in photocurrent density.
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Butcher, Brian J., and Chad B. O’Neal. "Piezoelectric PZT Semi-Ordered Nanotubes Arrays by Wetting of Porous Alumina Template." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-66825.

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Piezoelectric nanotubes are applicable to many areas including sensors, actuators, and energy storage. Before these applications can be realized using nanoscale components, a study is needed to characterize the piezoelectric-properties of nanotube geometries versus the piezoelectric-properties of a thin-film of the same material (not shown here). The material used in this study is (PZT) lead-zirconate-titanate, PbZr0.5Ti0.48O3. In this work, 200nm diameter PZT structures are manufactured by a template wetting procedure. These ceramic nanotubes are brittle but hold up well inside the alumina template structure. Having an array of nanometer-sized piezoelectric-tubes has been hypothesized to give comparable results to that of thin-films of the same material. The research described in this paper is a preliminary step towards testing this hypothesis via characterization and later producing piezoelectric-nanoscale-sensors, which are both small and efficient.
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Jankowski, Nicholas R., Andrew N. Smith, and Brendan M. Hanrahan. "Thermal Model of a Thin Film Pulsed Pyroelectric Generator." In ASME 2016 Heat Transfer Summer Conference collocated with the ASME 2016 Fluids Engineering Division Summer Meeting and the ASME 2016 14th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/ht2016-7437.

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Recent high energy density thin film material development has led to an increased interest in pyroelectric energy conversion. Using state-of-the-art lead-zirconate-titanate piezoelectric films capable of withstanding high electric fields we previously demonstrated single cycle energy conversion densities of 4.28 J/cm3. While material improvement is ongoing, an equally challenging task involves developing the thermal and thermodynamic process though which we can harness this thermal-to-electric energy conversion capability. By coupling high speed thermal transients from pulsed heating with rapid charge and discharge cycles, there is potential for achieving high energy conversion efficiency. We briefly present thermodynamic equivalent models for pyroelectric power generation based on the traditional Brayton and Ericsson cycles, where temperature-pressure states in a working fluid are replaced by temperature-field states in a solid pyroelectric material. Net electrical work is then determined by integrating the path taken along the temperature dependent polarization curves for the material. From the thermodynamic cycles we identify the necessary cyclical thermal conditions to realize net power generation, including a figure of merit, rEC, or the electrocaloric ratio, to aid in guiding generator design. Additionally, lumped transient analytical heat transfer models of the pyroelectric system with pulsed thermal input have been developed to evaluate the impact of reservoir temperatures, cycle frequency, and heating power on cycle output. These models are used to compare the two thermodynamic cycles. This comparison shows that as with traditional thermal cycles the Ericsson cycle provides the potential for higher cycle work while the Brayton cycle can produce a higher output power at higher thermal efficiency. Additionally, limitations to implementation of a high-speed Ericsson cycle were identified, primarily tied to conflicts between the available temperature margin and the requirement for isothermal electrical charging and discharging.
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