Chemical Modification of Alkoxide Precursors for Lead Zirconate Titanate Formation

1996 ◽  
Vol 49 (5) ◽  
pp. 569
Author(s):  
S Tursiloadi ◽  
H Imai ◽  
H Hirashima
Keyword(s):  
Lead Zirconate Titanate ◽  
Perovskite Phase ◽  
Pyrochlore Phase ◽  
Lead Zirconate ◽  
Significant Feature ◽  
Metal Alkoxide ◽  
Titanium Tetraisopropoxide ◽  
Zirconate Titanate ◽  
Diffraction Peaks ◽  
Alkoxide Precursors

Lead zirconate titanate (PZT) gel monolith was prepared by partially hydrolysing metal alkoxide solutions which were modified with acetylacetone ( acacH ). Lead diisopropoxide zirconium tetrabutoxide and titanium tetraisopropoxide were used as starting materials. After aging of the translucent monolithic gel at room temperature for several days or drying at 90°C for 18 h, the most significant feature in the infrared spectrum is the presence of bands at about 1550 cm-1 which can be assigned to the v(C-O) and v(C-C) vibrations of the acetylacetonate group coordinated to the metal cations of titanium and zirconium. Diffraction peaks of PbO were found after heating at 300°C for 2 h. After heating at 450°C for 2 h, diffraction peaks of pyrochlore Pb2Ti2O6 and perovskite PZT phases were observed. The diffraction peaks of PbO and the pyrochlore phase disappeared after heating at 600°C, and the tetragonal perovskite phase was stable up to 1000°C. Diffraction peaks of the perovskite phase were also found after heating at 430°C for 24 h.

Kinetics of formation of the pyrochlore and perovskite phases in sol-gel derived lead zirconate titanate powder

1998 ◽  
Vol 13 (8) ◽  
pp. 2170-2173 ◽  
Author(s):  
V. S. Tiwari ◽  
Arun Kumar ◽  
V. K. Wadhawan ◽  
Dhananjai Pandey
Keyword(s):  
Lead Zirconate Titanate ◽  
Perovskite Phase ◽  
Sol Gel ◽  
Pyrochlore Phase ◽  
Lead Zirconate ◽  
Oxygen Stoichiometry ◽  
X Ray ◽  
Zirconate Titanate ◽  
Kinetics Of Formation ◽  
Kinetics Of

Lead zirconate titanate (PZT) powder is prepared by the sol-gel method. The formation of pyrochlore and perovskite phases is investigated by high temperature x-ray diffraction (XRD) and thermal analysis techniques. The pyrochlore phase first appears in x-ray amorphous form, and then gets converted to crystalline state on annealing in air. We show that vacuum annealing of the pyrolyzed amorphous PZT gel suppresses the formation of the crystalline pyrochlore phase. This, in turn, enhances the kinetics of conversion of pyrochlore to perovskite, such that a pyrochlore-free perovskite phase can be obtained by annealing at about 500 °C. On the other hand, if annealing is carried out in air, a crystalline pyrochlore phase is formed, which requires annealing temperatures higher than 600 °C for transformation to the perovskite phase. These observations are explained tentatively in terms of the oxygen stoichiometry of the two phases.

Phase transformations in rapid thermal processed lead zirconate titanate

1995 ◽  
Vol 10 (12) ◽  
pp. 3149-3159 ◽  
Author(s):  
Ellen M. Griswold ◽  
L. Weaver ◽  
M. Sayer ◽  
I.D. Calder
Keyword(s):  
Thin Films ◽  
Lead Zirconate Titanate ◽  
Perovskite Phase ◽  
Sol Gel ◽  
Pyrochlore Phase ◽  
Lead Zirconate ◽  
Grain Structure ◽  
Avrami Model ◽  
Pzt Thin Films ◽  
Zirconate Titanate

The crystallization kinetics of the pyrochlore to perovskite phase transformation in lead zirconate titanate (PZT) thin films have been analyzed using rapid thermal processing (RTP). Sol-gel PZT thin films, fabricated on platinum electrodes, were annealed at 550 °C to 650 °C with hold times ranging from 1 s to 5 min. Glancing angle x-ray diffraction (XRD) was used for depth profiling to identify the location of phases in the films. Transmission electron microscopy (TEM) provided information on grain structure, nucleation, and growth. The phase information was correlated to the ferroelectric and dielectric properties. The perovskite phase nucleated in the pyrochlore phase throughout the film thickness, and at 650 °C the transformation was complete in 15 s. Fast growing (100) PZT nucleated at the platinum and consumed a small-grained matrix until a columnar structure was obtained. A ramp rate of 100 °C/s was sufficiently fast to prevent transformation during heating and allowed the direct application of an Avrami model for transformation kinetics. An activation energy of 610 kJ/mol was determined.

Effect of Pb Content on the Fatigue Properties of D.C. Reactive Sputtering-Derived PZT Thin Films

2006 ◽  
Vol 326-328 ◽  
pp. 613-616
Author(s):  
Dae Jin Yang ◽  
Seong Je Cho ◽  
Jong Oh Kim ◽  
Won Youl Choi
Keyword(s):  
Lead Zirconate Titanate ◽  
Perovskite Phase ◽  
Fatigue Behavior ◽  
Ferroelectric Properties ◽  
Pyrochlore Phase ◽  
Reactive Sputtering ◽  
Lead Zirconate ◽  
Fatigue Properties ◽  
Pzt Thin Films ◽  
Pzt Films

Lead zirconate titanate (Pb(Zr0.48Ti0.52)O3 or PZT) films were grown on platinized silicon wafers (Pt/SiO2/Si) by d.c. reactive sputtering method with multi targets. The Pb content of PZT films has been widely recognized as affecting not only the phase formation and microstructure but also the dielectric and ferroelectric properties. Pb content of PZT films was controlled by the variation of Pb target current. The relation between Pb content and Pb target current was expressed as y=0.89x-11.09. The x and y are Pb target current and Pb content, respectively. The pyrochlore phase was transformed to perovskite phase as Pb content was increased. This phase transformation improved the ferroelectric properties of PZT films. In PZT films with perovskite phase, fatigue properties were not improved with excess Pb content. Fatigue properties of PZT films began to be fatigued after 106 switching cycles and coincided with the typical PZT fatigue behavior. Excess Pb content (Pb vacancy) did not affect the fatigue properties of PZT films.

scholarly journals Perovskite phase formation and ferroelectric properties of the lead nickel niobate–lead zinc niobate–lead zirconate titanate ternary system

2003 ◽  
Vol 18 (12) ◽  
pp. 2882-2889 ◽  
Author(s):  
Naratip Vittayakorn ◽  
Gobwute Rujijanagul ◽  
Tawee Tunkasiri ◽  
Xiaoli Tan ◽  
David P. Cann
Keyword(s):  
Ternary System ◽  
Lead Zirconate Titanate ◽  
Remanent Polarization ◽  
Perovskite Phase ◽  
Ferroelectric Properties ◽  
Lead Zirconate ◽  
Zirconate Titanate ◽  
Lead Zinc Niobate ◽  
Lead Zinc ◽  
Lead Nickel

The ternary system of lead nickel niobate Pb(Ni1/3Nb2/3)O3 (PNN), lead zinc niobate Pb(Zn1/3Nb2/3)O3 (PZN), and lead zirconate titanate Pb(Zr1/2Ti1/2)O3 (PZT) was investigated to determine the influence of different solid state processing conditions on dielectric and ferroelectric properties. The ceramic materials were characterized using x-ray diffraction, dielectric measurements, and hysteresis measurements. To stabilize the perovskite phase, the columbite route was utilized with a double crucible technique and excess PbO. The phase-pure perovskite phase of PNN–PZN–PZT ceramics was obtained over a wide compositional range. It was observed that for the ternary system 0.5PNN–(0.5 - x)PZN–xPZT, the change in the transition temperature (Tm) is approximately linear with respect to the PZT content in the range x [H11505] 0 to 0.5. With an increase in x, Tm shifts up to high temperatures. Examination of the remanent polarization (Pr) revealed a significant increase with increasing x. In addition, the relative permittivity ([H9280]r) increased as a function of x. The highest permittivities ([H9280]r [H11505] 22,000) and the highest remanent polarization (Pr [H11505] 25 μC/cm2) were recorded for the binary composition 0.5Pb(Ni1/3Nb2/3)O3–0.5Pb(Zr1/2Ti1/2)O3.

Quantifying Domain Textures in Lead Zirconate Titanate Using 022:202 and 220 Diffraction Peaks

2005 ◽  
Vol 105 ◽  
pp. 379-384 ◽  
Author(s):  
Thomas Key ◽  
Jacob L. Jones ◽  
William F. Shelley ◽  
Keith J. Bowman
Keyword(s):  
Lead Zirconate Titanate ◽  
Single Phase ◽  
Lead Zirconate ◽  
Lead Magnesium Niobate ◽  
Zirconate Titanate ◽  
Lead Magnesium ◽  
Second Phases ◽  
Diffraction Peaks ◽  
Internal Strains

Determination of the domain textures in many lead zirconate titanate (PZT) piezoelectrics can be complicated by the presence of second phases, internal strains and small differences in lattice parameters for the commonly used 002 and 200:020 peaks. The domain texture is influenced by the applied polarization necessary for these materials to demonstrate piezoelectricity. In this paper we explore the use of 022:202 and 220 peaks for evaluating the domain textures and helping resolve the complexities of texture analysis in the presence of multiple phases. The two materials explored in this paper include a nominally single phase tetragonal PZT material and a mixed phase tetragonal-monoclinic lead magnesium niobate (PMN)-PZT alloy.

scholarly journals Orientation of rapid thermally annealed lead zirconate titanate thin films on (111) Pt substrates

1994 ◽  
Vol 9 (10) ◽  
pp. 2540-2553 ◽  
Author(s):  
Keith G. Brooks ◽  
Ian M. Reaney ◽  
Radosveta Klissurska ◽  
Y. Huang ◽  
L. Bursill ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Lead Zirconate Titanate ◽  
Pyrolysis Temperature ◽  
Pyrochlore Phase ◽  
Lead Zirconate ◽  
Zirconate Titanate ◽  
Excess Lead ◽  
Kinetics Of

The nucleation, growth, and orientation of lead zirconate titanate thin films prepared from organometallic precursor solutions by spin coating on (111) oriented platinum substrates and crystallized by rapid thermal annealing was investigated. The effects of pyrolysis temperature, post-pyrolysis thermal treatments, and excess lead addition are reported. The use of post-pyrolysis oxygen anneals at temperatures in the regime of 350–450 °C was found to strongly affect the kinetics of subsequent amorphous-pyrochlore-perovskite crystallization by rapid thermal annealing. The use of such post-pyrolysis anneals allowed films of reproducible microstructure and textures [both (100) and (111)] to be prepared by rapid thermal annealing. It is proposed that such anneals and pyrolysis temperature affect the oxygen concentration/average Pb valence in the amorphous films prior to annealing. Such changes in the Pb valence state then affect the stability of the transient pyrochlore phase and thus the kinetics of perovskite crystallization.

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