• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.183-187
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• 2007

$SiO_2/TiO_2$ core-shell particles with controlled shell thickness were prepared using large silica particles. The thickness of titania coating layer was varied from 8 nm to 38 nm depending on the number of coating steps from 1 to 3 times. After titania coating, the core-shell particles showed textured surface due to the titania coating layer, resulting in 3~25 times increase of specific surface areas. The properties of titania coated silica particles were characterized by FE-SEM, Zeta potential meter, BET, and XRD.

• Membrane Journal
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• v.21 no.3
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• pp.229-235
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• 2011

In this study, mesoporous titania/alumina membranes were prepared by sol-gel method. Pore structure and phase composition of titania/alumina membranes could be changed by calcination temperature. The addition of alumina into titania membranes retarded anatase-to-rutile phase transformation, resulting in stabilization of pore structures. The 5 time dip-coated membrane calcined at $450^{\circ}C$ is about $10.3{\mu}m$ in thickness with an average pore size of 5 nm. Hydrogen and nitrogen permeances through the membrane were $17.1{\times}10^{-7}mol/m^2{\cdot}s{\cdot}Pa$ and $4.7{\times}10^{-7}mol/m^2{\cdot}s{\cdot}Pa$, respectively. These data were explained by the Knudsen diffusion mechanism.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.3
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• pp.411-419
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• 2004

Titania particles are widely used as a photocatalyst to treat various contaminants in air and water. Titania particles were formed by vapor-phase oxidation of titanium tetraisopropoxide (TTIP) in a tube furnace between 773 and 1,273 K. The effect of process variables such as furnace temperature, flow rate of carrier air, and flow rate of sheath air on powder size and phase characteristics was investigated using a scanning mobility particle sizer (SMPS), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The size distribution of synthesized titania particles was characterized with mode diameter and peak concentration. The mode diameter ranging from 20 to 80 nm decreased with increasing flow rates of sheath air and carrier air, and increased with increasing furnace temperature. The peak concentration increased with increasing flow rates of sheath air and carrier air The best synthetic condition for high production rate can be derived from the experimental data set represented by mode diameter and peak concentration. The crystal structure of synthesized titania particles was found to be anatase phase, ensuring high photocatalytic potential.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.3
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• pp.240-245
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• 2013

The utilization of a fluoran leuco sensitizer, 2-anilino-6-dibutyl amino-3-methylfluoran (ODB-2), for dye-sensitized solar cells (DSSCs) was investigated through the examination of the adsorption of ODB-2 molecules onto the surfaces of porous titanium dioxide (titania, $TiO_2$) films and the photovoltaic properties of ODB-2-based DSSCs. Despite of the absence of the specific anchoring groups with titania, ODB-2 dye molecules were spontaneously adsorbed onto the titania surfaces because the lactone ring in ODB-2 was opened and changed into the carboxylic acid (-COOH) by releasing protons from the surfaces ($TiOH_2{^+}$) of titania, which consequently leads to the chemisorption reaction of ODB-2 molecules to the active sites of titania. DSSCs based on ODB-2 exhibited typical photovoltaic properties with an open-circuit voltage ($V_{OC}$) of 0.19 V, a short-circuit current ($J_{SC}$) of $0.30\;mA{\cdot}cm^{-2}$, a fill factor (FF) of 37%, and a conversion efficiency (PCE) of 0.02%.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.321-323
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• 2005

We report a microcapsule-based electronic ink display technique, containing hollow titania particles which were prepared via a complex coacervation method using gelatin and gum arabic. In order to reduce density mismatch between nanoparticels and dielectric medium, hollow titania particles were introduced. Microcapsules were then prepared using gelatin to improve the elasticity of the microcapsule wall and their electrophoretic characteristics were $investigated^1$

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.386-387
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• 2003

Titania-silica hybrid inorganic materials are interesting subjects and many researchers have been studying.$\^$1-3)/ In general, the titania-silica hybrid materials are used as film and catalyst. Sol-gel method has widely been used as an alternative technology to prepare a wide variety of applications including monoliths, powders, coatings, and fibers.$\^$4-6)/ The typical sol-gel method is hydrolysis and condensation of tetraethyl orthosilicate (TEOS), Si(OCH$_2$CH$_3$)$_4$. (omitted)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.03b
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• pp.20-20
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• 2010

We present a simple process for the fabrication of high performance transparent conducting films that contain single-walled carbon nanotubes (SWCNTs) noncovalently coated with an ultrathin titania layer. The hydrophobic interactions between nanotube surfaces and the acetylacetone (acac) ligands used to stabilize the $TiO_2$ precursor provide an interesting alternative method for noncovalently coating the SWCNTs with a titania layer. The ultrathin titania layer on SWCNTs prevented the oxidation of functionalized SWCNTs at high temperatures, and protected against water molecule absorption.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.279-279
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• 2010

We present a simple process for the fabrication of high performance transparent conducting films that contain single-walled carbon nanotubes (SWCNTs) noncovalently coated with an ultrathin titania layer. The hydrophobic interactions between nanotube surfaces and the acetylacetone (acac) ligands used to stabilize the $TiO_2$ precursor provide an interesting alternative method for noncovalently coating the SWCNTs with a titania layer. The ultrathin titania layer on SWCNTs prevented the oxidation of functionalized SWCNTs at high temperatures, and protected against water molecule absorption.

• Corrosion Science and Technology
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• v.5 no.6
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• pp.213-217
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• 2006

Titania coatings were prepared on commercially pure Ti by plasma electrolytic oxidation (PEO) method with various electrolytes and process condition. Coatings were formed under galvanostatic condition with several current density values, and the change of applied voltage with process time was recorded. The microstructure of the titania coatings was observed using XRD, SEM, TEM, and the time-voltage diagrams were analyzed in terms of microstructure evolution.

• Bulletin of the Korean Chemical Society
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• v.23 no.8
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• pp.1127-1134
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• 2002

Fine ceramic particles of zirconia toughened alumina (ZTA), titania toughened alumina (TTA), and zirconia-titania toughened alumina (ZTTA) have been synthesized by ultrasonic spray pyrolysis (USP) at various temperatures from starting salt solutio ns of various compositions aiming for the development of catalytic material. These particles were characterized for properties such as shape, size and size distribution, diffraction pattern, and chemical and phase composition of elements by scanning electron microscopy (SEM), particle size analyzer (PSA), x-ray diffraction (XRD), and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Chemical compositions and sizes of ceramic composites have been controled by the stoichiometry of salt solutions and the flow rate of spraying solutions. The optimum experimental conditions for the various composite particle syntheses have been proposed.