• Korean Journal of Materials Research
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• v.19 no.10
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• pp.555-561
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• 2009

Expanded graphite (EG) is synthesized by chemical intercalation of natural graphite (NG) and rapid expansion at high temperature, with titanium n-butoxide (TNB) used as titanium source by a sol-gel method to prepare EG-TiO$_2$ composite. The performances of the prepared EG-TiO$_2$ composite are characterized by BET surface area measurement, scanning electron microscopy (SEM), X-ray diffraction patterns (XRD) and energy dispersive X-ray analysis (EDX). To compare the photocatalytic activities of the EG-TiO$_2$ composite, three kinds of dye solutions, methylene blue (MB), methylene orange (MO) and rhodamine B (RhB), and two kinds of light source, UV light and visible light (VL), are used. Comparing the results, it can be clearly seen that the degradation of all of the dye solutions under irradiation by UV light is much better than that under irradiation by visible light, and the decomposition of MB solution was better than that of both of MO and RhB solution.

• Applied Chemistry for Engineering
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• v.17 no.2
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• pp.194-200
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• 2006

Titanium oxide films were deposited by the nozzle type HCP RT-MOCVD for the application of metal-oxide films. In the case of TTNB, after depositing films, films must be annealed at a proper temperature, but in the case of titanium ethoxide, titanium oxide films could be directly deposited by titanium ethoxide without general annealing. We could confirm that ratio of O to Ti in the films was about 2 : 1 at RF-power of 240 watt, distance between cathode and substrate of 3 cm, deposition time of 20 min, and ratio of Ar to $O_2$ of 1 : 1. Therefore, we could obtain the titanium oxide film deposited by the nozzle type HCP RT-MOCVD without an annealing process and could apply in the metal-oxide deposition process at a low temperature.

• Journal of the Korean Ceramic Society
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• v.45 no.11
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• pp.651-657
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• 2008

In this study, CNT/$TiO_2$ composites were prepared using surface modified Multiwall carbon nanotube (MWCNT) and titanium n-butoxide (TNB) with benzene. The composites were characterized by nitrogen adsorption isotherms, scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX), FT-IR spectra, and UV-vis absorption spectroscopy. The UV radiation induced photoactivity of the CNT/$TiO_2$ composites was tested using a fixed concentration of methylene blue (MB, $C_{16}H_{18}N_3S{\cdot}Cl{\cdot}3H_2O$) in an aqueous solution. Finally, it can be considered that the MB removal effect of the CNT/$TiO_2$ composites is not only due to the adsorption effect of MWCNT and photocatalytic degradation of $TiO_2$, but also to electron transfer between MWCNT and $TiO_2$.

• Carbon letters
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• v.8 no.3
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• pp.177-183
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• 2007

[ $TiO_2$ ]ACF composites were prepared by the electrochemical method with Titanium (IV) n-butoxide (TNB) electrolyte under different electrochemical operation time. The BET surface area for $TiO_2$/ACF composites decrease with the increase of electrochemical operation time. There is a single crystal structure which is anatase in all of the samples from the data of XRD. The SEM micrphotographs of $TiO_2$/ACF composites show that the $TiO_2$ particles were well mixed with the ACF. There are O and P with strong C and Ti peaks in all samples from EDX results, and it also shows that a decrease of the C content with a increasing of Ti content with increasing of the electrochemical operation time in the over all composites. DSC cures show that the exothermic peak of all composites at $560^{\circ}C$ represents the transformation heat of amorphous parts to anatase phase and the discontinuous grain growth of the transformed anatase particles. Finally, the excellent photoactivity of $TiO_2$/ACF composites (especially, ACFT10) could be attributed that the decrease of concentration of MB can be concluded to be much faster for the adsorption by ACF than for photocatalytic decomposition by $TiO_2$.

• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1463-1466
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• 2007

Single phases of multi-component oxides films, ZrTiO4 and Ta2Zr6O17, could be synthesized by using the combinatorial approach through surface sol-gel route, coating the appropriate mole ratio of 100 mM zirconium butoxide, tantalum butoxide and titanium butoxide precursors on Pt/Ti/SiO2/Si (100) substrate, following pyrolysis at 450 oC, and annealing them at 770 oC. Both the films and bulks of ZrTiO4 and Ta2Zr6O17 showed very stable dielectric properties in temperature range, ?140 to 60 oC, and frequency range, 100 Hz to 1 MHz, promising their applications in wide range of temperatures and frequencies. The dielectric constants of the films were lower and a little more dependent on frequency than those of the bulks. The reduction of dielectric property in the film was mainly due to the interfacial effects that worked as series and parallel-connected capacitances toward the substantial film capacitance.

• Korean Journal of Materials Research
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• v.20 no.7
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• pp.345-350
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• 2010

For the present paper, we prepared MgO/MWCNT/$TiO_2$ photocatalyst by using multi-walled carbon nanotubes (MWCNTs) pre-oxidized by m-chlorperbenzoic acid (MCPBA) with magnesium acetate tetrahydrate $(Mg(CH_2COO)_2\cdot4H_2O)$ and titanium n-butoxide $(Ti\{OC(CH_3)_3\}_4)$ as magnesium and titanium precursors. The prepared photocatalyst was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. The decomposition of methylene blue (MB) solution was determined under irradiation of ultraviolet (UV) light. The XRD results show that the MgO/MWCNT/$TiO_2$ photocatalyst have cubic MgO structure and anatase $TiO_2$ structure. The porous structure and the $TiO_2$ agglomerate coated on the MgO/MWCNT composite can be observed in SEM images. The Mg, O, Ti and C elements can be also observed in MgO/MWCNT/$TiO_2$ photocatalyst from EDX results. The results of photodegradation of MB solution under UV light show that the concentration of MB solution decreased with an increase of UV irradiation time for all of the samples. Also, the MgO/MWCNT/$TiO_2$ photocatalyst has the best photocatalytic activity among these samples. It can be considered that the MgO/MWCNT/$TiO_2$ photocatalyst had a combined effect, the effect of MWCNT, which could absorb UV light to create photoinduced electrons $(e^-)$, and the electron trapping effect of MgO, which resulted in an increase of the photocatalytic activity of $TiO_2$.

• Journal of the Korean Ceramic Society
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• v.56 no.1
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• pp.98-103
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• 2019

Optical filters to control light wavelength of displays or cameras are fabricated by multi-layer stacking process of low and high index thin films. The process of multi-layer stacking of thin films has received much attention as an optimal process for effective manufacturing in the optical filter industry. However, multi-layer processing has disadvantages of complicated thin film process, and difficulty of precise control of film morphology and material selection, all of which are critical for transmittance and coloring effect on filters. In this study, the composite $TiO_2$, which can be used to control of UV absorption, coated on nano hollow silica sol, was synthesized as a coating material for optical filters. Furthermore, systematic analysis of the process parameters during the chemical reaction, and of the structural properties of the coating solutions was performed using SEM, TEM, XRD and photo spectrometry. From the structural analysis, we found that the 85 nm nano hollow silica with 2.5 nm $TiO_2$ shell formation was successfully synthesized at proper pH control and titanium butoxide content. Photo luminescence characteristics, excited by UV irradiation, show that stable absorption of 350 nm-light, correlated with a 3.54 eV band gap, existed for the $TiO_2$ shell-nano hollow silica reacted with 8.8 mole titanium butoxide solution. Transmittance observed on substrate of the $TiO_2$ shell-nano hollow silica showed effective absorption of 200-300 nm UV light without deterioration of visible light transparency.

• Polymer(Korea)
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• v.36 no.1
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• pp.47-52
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• 2012

Abstract: In this study, PAN/$TiO_2$ fiber mats were fabricated from polyacrylonitrile (PAN) and titanium(IV) butoxide ($Ti(OBu)_4$) by an electrospinning method with various solution concentrations, applied voltages and solution flow rates. The fiber mats were irradiated with an electron beam to induce structural crosslinking and enhance photocatalytic activity. As a result, uniform and bead-free fibers without pits or cracks on surface were obtained at 5 wt% of $Ti(OBu)_4$ solution with 15 kV and 0.02 mL/min flow rate. The PAN/$TiO_2$ fiber mats were irradiated with an electron beam of 1.14 MeV acceleration voltage, 4 mA of current and $1{\times}10^4kGy$. Electron beam irradiation was enhanced the photocatalytic activity of PAN/$TiO_2$ nano fiber mat. The photocatalytic activity of the PAN/$TiO_2$ fiber mat was analyzed by degradation of methylene blue and volatile organic compounds.

• Journal of the Korean Ceramic Society
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• v.45 no.11
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• pp.667-674
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• 2008

In this study, we prepared Fe-activated carbon fiber(ACF)/$TiO_2$ composites with titanium (VI) n-butoxide (TNB) as the titanium source for ACF pre-treated with iron compounds through the impregnation method. In terms of textural surface properties, the composites demonstrate a slight decrease in the BET surface area of the samples and an increase in the amount of iron compounds treated. The surface morphology of the Fe-ACF/$TiO_2$ composites was characterized by means of SEM. The composites have a porous texture with homogenous compositions of Fe and titanium dioxide distributed on the sample surfaces. The phase formation and structural transition of the iron compounds and titanium dioxide were observed in X-ray diffraction patterns of the Fe-ACF/$TiO_2$ composites. The chemical composition of the Fe-ACF/$TiO_2$ composites, which was investigated with EDX shows strong peaks for the C, O, Fe and Ti elements. The photo degradation results confirm that the Fe-ACF/$TiO_2$ composites show excellent removal activity for the COD in piggery waste due to photocatalysis of the supported $TiO_2$, radical reaction by Fe species, and the adsorptivity and absorptivity of ACF.

• Journal of the Korean Ceramic Society
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• v.33 no.7
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• pp.755-760
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• 1996

Sol-gel processing was used to prepare PZT fibers. Titanium isopropoxide Zirconium n-butoxide and lead acetate trihydrate were used as starting materials and TEA(triethanolamine) was added to form stabilized Pb-Ti-Zr complex alkoxide, Effects of catalysts and various solvents on the state of precursor sol gelation reaction fiber spinnability pyrolysis and crystallization were also investiated.