Structural and Functional Properties of Fluorinated Silica Hybrid Barrier Layers on Flexible Polymeric Foil

The reported work was focused on sol–gel-derived organically modified and fluorinated silica coatings deposited on elastic polymeric foil. The structure and topography of the coatings were tested by infrared spectroscopy and microscopic studies. The functional properties were determined using thermal analysis, surface analysis, and oxygen permeability tests. The barrier feature of the investigated materials against oxygen was correlated with the properties of the coatings. The hybrid (organic–inorganic) structure of the coatings was proven, demonstrating the presence of a silica network modified with alkyl and fluoroalkyl groups since precursors with the isooctyl group or different lengths of the fluoroalkyl chains were used for the syntheses. The coatings were free of defects and had a smooth surface except for the sample containing the longest fluoroalkyl chain (perfluorododecyl group), which showed a wrinkle-like surface. The hydrophobic character of the coatings increased, whereas the oxygen permeation coefficient values decreased (reaching a fourfold lower coefficient in comparison to the bare substrate) with a higher content of the fluorinated carbon atoms in the structure. The results were enriched by the information from the thermomechanical analysis as well as nanoindentation and scratch tests giving values of the glass transition temperature, thermal expansion coefficient, coatings adhesion, and hardness of the investigated systems.

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Structural and functional properties of sol-gel synthesized and microwave heated Pb0.8 Co0.2-zLazTiO3 (z = 0.05–0.2) nanoparticles

Ceramics International ◽

10.1016/j.ceramint.2018.07.176 ◽

2018 ◽

Vol 44 (16) ◽

pp. 19408-19420 ◽

Cited By ~ 35

Author(s):

N. Suresh Kumar ◽

R. Padma Suvarna ◽

K. Chandra Babu Naidu ◽

G. Ranjith Kumar ◽

S. Ramesh

Keyword(s):

Functional Properties ◽

Sol Gel ◽

Structural And Functional Properties

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Effect of Praseodymium Species on the Structural and Functional Properties of Nanocrystalline BiFeO3 Powders and Thin Films

MRS Proceedings ◽

10.1557/opl.2012.1067 ◽

2012 ◽

Vol 1454 ◽

pp. 39-44

Author(s):

Gina Montes Albino ◽

Marco Gálvez-Saldaña ◽

Oscar Perales-Pérez

Keyword(s):

Thin Films ◽

Crystallite Size ◽

Functional Properties ◽

Doping Level ◽

Sol Gel ◽

Average Crystallite Size ◽

Gel Method ◽

Sol Gel Method ◽

Ferroelectric Behavior ◽

Structural And Functional Properties

ABSTRACTThe present study addressed the effect of the incorporation of Praseodymium species in the BiFeO3(BFO) structure on the corresponding structural and functional properties of powders and films. The level of the doping species varied from 0 at% to 4 at%. BFO powders and thin films were synthesized by a sol-gel method, where glycol was aggregated to the main solvent to increase the viscosity of the precursor solutions and promote their adhesion onto platinum substrates. The development of the host BFO structure was confirmed by XRD analyses of samples annealed at 700°C for one hour (powders) or 500°C for 2 hours (thin films), in air. The average crystallite size varied from 37 nm to 41 nm and 28nm to 40nm for powders and thin films, respectively, due to the increase of the doping level. The incorporation of specific dopant species played an important role in the ferromagnetic and ferroelectric behavior in the material.

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Effect of Ca and Ag doping on the functional properties of BiFeO3 nanocrystalline powders and films

MRS Proceedings ◽

10.1557/opl.2014.778 ◽

2014 ◽

Vol 1675 ◽

pp. 105-111 ◽

Cited By ~ 1

Author(s):

Gina Montes Albino ◽

Oscar Perales-Pérez ◽

Boris Renteria-Beleño ◽

Yarilyn Cedeño-Mattei

Keyword(s):

Thin Films ◽

Functional Properties ◽

Bismuth Ferrite ◽

Sol Gel ◽

Magnetic Behavior ◽

Nitrogen Atmosphere ◽

Nanocrystalline Powders ◽

Systematic Evaluation ◽

Gel Method ◽

Structural And Functional Properties

ABSTRACTThe present work addresses the systematic evaluation of the influence of the incorporation of dopant species (Ca+2, Ag+1) on the structural and functional properties of bismuth ferrite (BFO) nanocrystalline powders and films. Pure and doped BFO powders and thin films were synthesized by a modified sol-gel method. The concentration of the doping species varied from 0 up to 7 at %. The development of the host BFO structure was confirmed by XRD analyses of samples annealed at 700°C for one hour in air and nitrogen atmosphere. Thicknesses of films varied between 80 and 200 nm, depending on the concentration of Ca+2 species. Doped BFO exhibited a magnetic behavior that turned from paramagnetic into ferrimagnetic with the increase of Ca+2 concentrations.

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Inorganic-Organic Composites by Sol-Gel Techniques

MRS Proceedings ◽

10.1557/proc-171-3 ◽

1989 ◽

Vol 171 ◽

Cited By ~ 31

Author(s):

Helmut Schmidt

Keyword(s):

Functional Properties ◽

Structural Modification ◽

Sol Gel ◽

Surface Hardness ◽

Structural And Functional Properties ◽

Sol Gel Process ◽

Polymeric Chains ◽

Organically Modified ◽

Structural Surface ◽

Inorganic Organic Polymers

ABSTRACTThe sol-gel process opens the possibility of combining inorganic and organic units to new hybrid polymers. Organic units can be used for structural modification of the inorganic backbone, for creating new functions within an inorganic network and for building up organic polymeric chains. The materials show interesting perspectives with respect to structural (surface hardness, strength) and functional properties (e. g. diffusion, photocuring, incorporation of dyes, optical properties). A review over structural and functional properties of sol-gel derived inorganic-organic polymers (ORMOCERs = organically modified ceramics) is given.

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