Effect of sintering conditions on the pyrochlore phase content in PMN–PFN ceramics prepared by sol–gel process

Lead iron niobate Pb(Fe0.5Nb0.5)O3 (PFN) ceramics were prepared using sol-gel synthesis by mixing acetates Pb and Fe with Nb-ethylene glycol-tartarate (Pechini) complex at 80°C, calcination of gels at 600°C and sintering at 1150°C for various times. The metastable pyrochlore phase Pb3Nb4O13 in stoichiometric precursor was partially decomposed to perovskite phase Pb(Fe0.5Nb0.5)O3 in ceramics sintered at temperature of 1150°C for 2, 4 and 6 hours. Excess of Pb in molar ratio (Pb:Fe:Nb = 1.2:0.5:0.5) caused the increase of the content of the perovskite phase (~50 vol.%) in nonstoichiometric PFN ceramics sintered at 1150°C for 6 hours while the decrease in perovskite phase content was found in stoichiometric PFN ceramics (~16 vol.%). In microstructures of PFN ceramics sintered at 1150°C for different times, the bimodal grain size distribution was observed with small spherical grains of perovskite phase and larger octahedral grains of pyrochlore phase. EDX analysis confirm that complex types of pyrochlore phases that differ in iron content were present in ceramics.

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Influence of sintering conditions on the resistance and structure of YBa2Cu3O7−x ceramics prepared by the sol-gel process

Journal of Materials Science Letters ◽

10.1007/bf01729968 ◽

1989 ◽

Vol 8 (8) ◽

pp. 979-980 ◽

Cited By ~ 4

Author(s):

P. Diko ◽

I. Žežula ◽

I. Batko ◽

V. Kavečanský ◽

K. Csach ◽

...

Keyword(s):

Sol Gel ◽

Sol Gel Process ◽

Sintering Conditions

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Preparation and Characterization of Metal Alkoxide Derived Epitaxial Lead Titanate Based Thin Films

MRS Proceedings ◽

10.1557/proc-361-415 ◽

1994 ◽

Vol 361 ◽

Author(s):

Keiichi Nashimoto ◽

Shigetoshi Nakamura

Keyword(s):

Thin Films ◽

Lead Titanate ◽

Solid Phase ◽

Sol Gel ◽

Pyrochlore Phase ◽

Guided Wave ◽

Metal Alkoxide ◽

Rocking Curve ◽

Sol Gel Process

ABSTRACTEpitaxial and highly oriented lead titanate based thin films were prepared by a sol-gel process using non-hydrolyzed methoxyethoxide precursors and RTA process. PbTiO3 crystallized with preferred (001) or (100) orientation on SrTiO3 (100) and MgO (100). Solid phase (001) oriented epitaxial growth of PZT on SrTio3 was observed at 425°C, directly from the amorphous phase. That of PZT on MgO was observed at temperatures above 550°C, after the formation of pyrochlore phase. The PZT on SrTiO3 had a single (001) orientation and rocking curve full width at half maximum less than 0.08°. PZT showed a weak preferred (111) orientation on sapphire (0001) substrates, while highly (111) oriented PLT thin films were obtained on them. The guided wave modes were excited by a prism coupling for PZT thin films crystallized on SrTiO3 and MgO. Electrical properties of epitaxial PZT and PLT thin films on Nb-SrTiO3 substrates were characterized.

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The crystallization of thin-film ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122095 ◽

1992 ◽

Vol 50 (1) ◽

pp. 338-339

Author(s):

J.M. Schwartz ◽

L.F. Francis ◽

L.D. Schmidt ◽

P.S. Schabes-Retchkiman

Keyword(s):

Thin Films ◽

Grain Size ◽

Sol Gel ◽

Processing Route ◽

Small Areas ◽

Ceramic Thin Films ◽

Complex Shapes ◽

Sol Gel Process ◽

Ceramic Precursors ◽

Crystalline Ceramic

Ceramic thin films and coatings are of interest for electrical, optical, magnetic and thermal barrier applications. Critical for improved properties in thin films is the development of specific microstructures during processing. To this end, the sol-gel method is advantageous as a versatile processing route. The sol-gel process involves depositing a solution containing metalorganic or colloidal ceramic precursors onto a substrate and heating the deposited layer to form a crystalline or non-crystalline ceramic coating. This route has several advantages, including the ability to create tailored microstructures and properties, to coat large or small areas, simple or complex shapes, and to more easily prepare multicomponent ceramics. Sol-gel derived coatings are amorphous in the as-deposited state and develop their crystalline structure and microstructure during heat-treatment. We are particularly interested in studying the amorphous to crystalline transformation, because many key features of the microstructure such as grain size and grain size distribution may be linked to this transformation.

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Epitaxial Growth of Sr0.3Ba0.7Nb2O6 Thin Films Prepared by Sol-Gel Process

MRS Proceedings ◽

10.1557/proc-606-181 ◽

1999 ◽

Vol 606 ◽

Cited By ~ 2

Author(s):

Keishi Nishio ◽

Jirawat Thongrueng ◽

Yuichi Watanabe ◽

Toshio Tsuchiya

Keyword(s):

Thin Film ◽

Thin Films ◽

Epitaxial Growth ◽

Raw Materials ◽

Substrate Surface ◽

Sol Gel ◽

Tungsten Bronze ◽

Monomethyl Ether ◽

Tetragonal Tungsten Bronze ◽

Sol Gel Process

AbstructWe succeeded in the preparation of strontium-barium niobate (Sr0.3Ba0.7Nb2O6 : SBN30)that have a tetragonal tungsten bronze type structure thin films on SrTiO3 (100), STO, or La doped SrTiO3 (100), LSTO, single crystal substrates by a spin coating process. LSTO substrate can be used for electrode. A homogeneous coating solution was prepared with Sr and Ba acetates and Nb(OEt)5 as raw materials, and acetic acid and diethylene glycol monomethyl ether as solvents. The coating thin films were sintered at temperature from 700 to 1000°C for 10 min in air. It was confirmed that the thin films on STO substrate sintered above 700°C were in the epitaxial growth because the 16 diffraction spots were observed on the pole figure using (121) reflection. The <130> and <310> direction of the thin film on STO were oriented with the c-axis in parallel to the substrate surface. However, the diffraction spots of thin film on LSTO substrate sintered at 700°C were corresponds to the expected pattern for (110).

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UV Curable Organic-Inorganic Hybrid Materials

MRS Proceedings ◽

10.1557/proc-628-cc6.14 ◽

2000 ◽

Vol 628 ◽

Cited By ~ 1

Author(s):

Guang-Way Jang ◽

Ren-Jye Wu ◽

Yuung-Ching Sheen ◽

Ya-Hui Lin ◽

Chi-Jung Chang

Keyword(s):

Hybrid Materials ◽

Colloidal Silica ◽

Sol Gel ◽

Solution Ph ◽

Uv Curable ◽

Inorganic Hybrid ◽

Degradation Temperature ◽

Sol Gel Process ◽

The Stability ◽

Thermal Degradation Temperature

This work successfully prepared an UV curable organic-inorganic hybrid material consisting of organic modified colloidal silica. Applications of UV curable organic-inorganic hybrid materials include abrasion resistant coatings, photo-patternable thin films and waveguides. Colloidal silica containing reactive functional groups were also prepared by reacting organic silane and tetraethyl orthosilicate (TEOS) using sol-gel process. In addition, the efficiency of grafting organic moiety onto silica nanoparticles was investigated by applying TGA and FTIR techniques. Experimental results indicated a strong interdependence between surface modification efficiency and solution pH. Acrylate-SiO2 hybrid formation could result in a shifting of thermal degradation temperature of organic component from about 200°C to near 400°C. In addition, the stability of organic modified colloidal silica in UV curable formula and the physical properties of resulting coatings were discussed. Furthermore, the morphology of organic modified colloidal silica was investigated by performing TEM and SEM studies‥

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Halogenation of ORMOSIL: A Promising Rout for Tailoring Optical Absorptions

MRS Proceedings ◽

10.1557/proc-771-l4.1 ◽

2003 ◽

Vol 771 ◽

Author(s):

Amir Fardad ◽

Wei Liang ◽

Yadong Zhang ◽

Bryson Case ◽

Shibin Jiang ◽

...

Keyword(s):

Process Parameters ◽

Sol Gel ◽

Fiber Amplifiers ◽

Grignard Reaction ◽

Coupling Loss ◽

Beam Splitters ◽

Silicon Technology ◽

Sol Gel Process ◽

Propagation Losses ◽

Signal Intensities

AbstractFluorinated and photo-imageable precursors are synthesized through a Barbier-Grignard reaction for 1550-nm window. The precursors are used for the sol-gel process of integrated optic components for silica-on-silicon technology. Material compositions and process parameters are optimized to achieve internal absorptions >0.1 dB/cm and propagation losses of about 0.5 dB/cm at 1550 nm. Compact 1×16 Beam splitters are designed and fabricated which exhibit >0.3 dB power uniformity, >0.1 dB PDL and 1.5 dB coupling loss. By hybrid integration of the passive splitters and in-house fiber amplifiers, amplifying splitters are demonstrated at various signal intensities.

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