• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.212.2-212
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• 2003

• Proceedings of the Optical Society of Korea Conference
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• 2008.07a
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• pp.209-210
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• 2008

• Proceedings of the Optical Society of Korea Conference
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• 2008.07a
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• pp.211-212
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• 2008

• Proceedings of the Optical Society of Korea Conference
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• 2008.07a
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• pp.213-214
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• 2008

• Journal of Soil and Groundwater Environment
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• v.12 no.3
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• pp.29-35
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• 2007

Titanium was oxidized with oxygen plasma and calcinated with rapid thermal annealing for degradation of humic acid dissolved in water. Titania photocatalytic plate was produced by titanium surface oxidized with oxygen plasma by Plasma Enhanced Chemical Vapor Deposition (PECVD). RF-power and deposition condition is controlled under 100 W, 150 W, 300 W and 500 W. Treatment time was controlled by 5 min and 10 min. The film properties were evaluated by the X-ray Photoelectron Spectroscopy (XPS) and X-Ray Diffraction (XRD). From the experimental results, we found the optimal condition of titania film which exhibited good performance. Moreover photocatalytic capacity was about twice better than thermal spray titania film, and also as good as titania powder.

• Particle and aerosol research
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• v.5 no.1
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• pp.1-7
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• 2009

Fe- and V-doped titanium dioxide nanoparticles consisting of spherical primary nanoparticles were synthesized from a mixed liquid precursor by using the flame spray pyrolysis. The effects of dopant concentration on the powder properties such as morphology, crystal structure, and light adsorption were analyzed by TEM, XRD, and UV-Vis spectrophotometer, respectively. As the V/Ti molar ratio increased, pure anatase particles were synthesized. On the contrary, rutile phase particles were synthesized as the Fe/Ti ratio increased. Photocatalytic property of as-prepared $TiO_2:Fe,V$ nanoparticles was investigated by measuring the removal efficiency for volatile organic compounds (VOCs) under the irradiation of visible light. After 2 hrs under visible light, the removal efficiencies of benzene, p-xylene, ethylbenzene, and toluene were reached to 21.9%, 21.4%, 19.8% and 17.6% respectively.

• Journal of the Korean Ceramic Society
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• v.49 no.1
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• pp.130-133
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• 2012

In this work we report investigation results of enhanced visible light photocatalytic properties of CdS and CdSe sensitized $TiO_2$ nanotube heterostructures. Anodically grown ordered $TiO_2$ nanotube arrays were sensitized with CdS and CdSe by using successive ionic layer adsorption and reaction method. Photocatalytic measurements revealed that heterostructured samples show enhanced photocurrent density under the visible light illumination. Improved visible light performance of the heterostuctures was explained by lower band gap of the CdS and CdSe and their favorable conduction band positions relative to $TiO_2$. Moreover, due to the lower band gap of the CdSe (1.7 eV) compared to CdS (2.4 eV), both photocurrent density and photoconversion efficiency results showed superior activity.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.425.2-425.2
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• 2014

$TiO_2$ possesses great photocatalytic properties but absorbs only UV light owing to high band gap energy (Eg = 3.2 eV). By narrowing the band gap through doping a metal ion, the photocatalytic activity can be enhanced in condition of the light of a higher than 365 nm wavelength. Main purpose for this study is to evaluate the activities of metal doped $TiO_2$ for degrading the volatile organic compounds (VOCs); p-xylene is chosen in the VOC removal test. Vanadium is selected in this study because an ionic radius of vanadium is almost the same as titanium ion and vanadium can be easily doped into $TiO_2$. V-doped $TiO_2$ was synthesized by sol-gel methods and compared with pure $TiO_2$. Pure TiO2 powder and V-doped $TiO_2$ powder were coated on glasses by spray coating method. UV-Visible spectrophotometer was used for the measurement of the band gap changes. VOC concentration degradation level was tested with using various UV light sources in an enclosed chamber. Catalytic activities of prepared samples were evaluated based on the experimental results and compared with coated pure $TiO_2$ sample.

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.38.1-38.1
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• 2010

Nanofibers have a large potential in air filtration applications. In this work, we have developed a photocatalytic polyvinyl alcohol PVA/$TiO_2$ nanofibers membrane for the treatment of air filtration by using electrospinning method. PVA were electrospun into nanofibrous membranes and $TiO_2$ nanoparticles were loaded in PVA nanofibers in various contents from 10% (w/w) to 50% (w/w). The UV-Vis spectra were conducted for testing the existence of $TiO_2$ nanoparticles in PVA fibers. SEM analysis indicated that $TiO_2$ nanoparticles were loaded on the surface of PVA fibers and dispersed linearly along the fiber direction, which originated from the effect of polarization and orientation caused by high electric field. X-ray diffraction (XRD) was used to determine the crystalline of the membrane. Tensile strength was measured to evaluate the physical properties of the membrane. Therefore, our work suggested that PVA/$TiO_2$ nanofiber membrane has a potential application in air filtration area.

• Korean Journal of Materials Research
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• v.27 no.5
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• pp.289-293
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• 2017

$Y_2Ti_2O_7$ nanoparticles (0.3 mol%) have been successfully synthesized by the co-precipitation process. The samples, adjusted to pH7 with ammonia solution as catalyst and calcined at $700{\sim}900^{\circ}C$, exhibit very fine particles with close to spherical shape and average size of 10-30 nm. It was possible to control the size of the synthesized $Y_2Ti_2O_7$ particles by manipulating the conditions. The $Y_2Ti_2O_7$ nanoparticles were coated on a glass substrate by a dipping coating process with inorganic binder. The $Y_2Ti_2O_7$ solution coated on the glass substrate had excellent adhesion of 5B; pencil hardness test results indicated an excellent hardness of 6H. The thickness of the thick film was about $30{\mu}m$. Decomposition of MB on the $Y_2Ti_2O_7$ thin film shows that the photocatalytic properties were excellent.