• Title/Summary/Keyword: titanium n-butoxide

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The Photodegradation Effect of Organic Dye for Metal Oxide (Cr2O3, MgO and V2O3) Treated CNT/TiO2 Composites

  • Chen, Ming-Liang;Bae, Jang-Soon;Yoon, Hee-Seung;Lim, Chang-Sung;Oh, Won-Chun
    • Bulletin of the Korean Chemical Society
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    • v.32 no.3
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    • pp.815-820
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    • 2011
  • Three kinds of organometallic compounds (chromium acetylacetonate, magnesium acetate and vanadyl acetylacetonate) were used as transition metal precursor, titanium n-butoxide and multi-walled carbon nanotube as titanium and carbon precursor to prepare metal oxide-CNT/$TiO^2$ composites. The surface properties and morphology of metal oxide-CNT/$TiO^2$ composites were by Brauer-Emett-Teller (BET) surface area measurement, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive X-ray (EDX) analysis. The photocatalytic activity of prepared metal oxide-CNT/$TiO^2$ composites was determined by the degradation effect of methylene blue in an aqueous solution under irradiation of visible light.

Synthesis and Characterization of Fe-fullerene/TiO2 Photocatalysts Designed for Degradation of Methylene Blue

  • Meng, Za-Da;Zhang, Kan;Oh, Won-Chun
    • Korean Journal of Metals and Materials
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    • v.48 no.7
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    • pp.674-682
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    • 2010
  • Fe-fullerene/$TiO_2$ composite photocatalysts were prepared with titanium (IV) n-butoxide (TNB) by a sol-gel method. The samples were characterized by scanning electron microscopy (SEM), Transmission electron microscope (TEM), specific surface area (BET), X-ray diffraction analysis (XRD) and energy dispersive X-ray spectroscopy (EDX). The photocatalytic activities were evaluated by the photocatalytic degradation of methylene blue (MB) solution. XRD patterns of the composites showed that the Fe-fullerene/$TiO_2$ composite contained a typical single and clear anatase phase. The surface properties shown by SEM present a characterization of the texture on Fe-fullerene/$TiO_2$ composites and showed a homogenous composition in the particles for the titanium sources used. The EDX spectra for the elemental identification showed the presence of C and Ti with strong Fe peaks for the Fe-fullerene/$TiO_2$ composite. From the photocatalytic results, the excellent activity of the Fe-fullerene/$TiO_2$ composites for degradation of methylene blue under UV light irradiation could be attributed to both the effects between photocatalytic reaction of the supported $TiO_2$, decomposition of the organometallic reaction by the Fe compound and energy transfer effects such as electron and light of the fullerene.

Preparation and photocatalytic effect of MWCNT/TiO2 composites (MWCNT/TiO2 복합체의 제조 및 광촉매 특성)

  • Chen, Ming-Liang;Oh, Won-Chun
    • Analytical Science and Technology
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    • v.21 no.3
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    • pp.229-236
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    • 2008
  • $C/TiO_2$ composites were prepared with surface modified MWCNT sequentially after HCl treatment and TNB as titanium source. There is a single crystal structure which is anatase in all of the samples from the data of XRD. The SEM microphotographs of $C/TiO_2$ composites show that the $TiO_2$ particles were well mixed with the CNT. There are C, O and Al with strong Ti peaks in all samples from EDX results, and it also shows that the sample CT has much more amount of C and Ti content than that of sample HCT. Finally, the photocatalytic activities for the $C/TiO_2$ composites have more effective than that of pristine $TiO_2$.

Highly Donor-doped LaxBa1-xTiO3 Ceramics

  • Korobova Nataly;Soh Dea-Wha
    • Transactions on Electrical and Electronic Materials
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    • v.4 no.4
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    • pp.18-21
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    • 2003
  • Sol-gel processing of $BaTiO_3$ ceramics doped with La(0.01-1.00 at. $\%$) were prepared from metal barium, titanium n-butoxide and lanthanum iso-propoxide. Characterization of the sol-gel-derived powder using XRD, SEM is also reported. The obtained results showed that insulator to semiconductor transition for highly donor-doped barium titanate was closely related to the incorporation of donor into the grains and to the resultant grain size, which were significantly affected by the sinterability of $BaTiO_3$ powders and sintering conditions used.

Comparison of physical properties and dye photo-degradation effects for $carbon/TiO_2$ complexes

  • Oh, Won-Chun;Lim, Chang-Sung
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.17 no.5
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    • pp.196-203
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    • 2007
  • We have studied a method for the preparation of hybrid $carbon/TiO_2$ complexes involving pitch coating, pitch binding and the penetration of titanium n-butoxide(TNB) solution with porous carbon. The photocatalysts were investigated with surface textural properties and SEM morphology, structural crystallinity and elemental identification between porous carbon and $TiO_2$, and dye decomposition performance. For the all $carbon/TiO_2$ complexes prepared by some kinds of different methods, the excellent photocatalytic effect for dye degradation should be attributed to the both effects between photo-decomposition of the supported $TiO_2$ and adsorptivity of the porous carbons.

The Electrochemical Properties of Li4/3Ti5/3O4 Synthesized by Sol-Gel Process (졸-겔법에 의해 합성된 Li4/3Ti5/3O4의 전기화학적 특성)

  • Lee, Jin-Sik;Lee, Chul-Tae
    • Applied Chemistry for Engineering
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    • v.10 no.1
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    • pp.73-79
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    • 1999
  • The superstructured $Li_{4/3}Ti_{5/3}O_4$ was prepared by sol-gel process using a mixed solution of lithium acetate (LA) and titanium n-butoxide (TNB). The gel phase was obtained by adding ammonia water ($NH_4OH/TNB$ mole ratio of 0.35) and water ($H_2O/TNH$ mole ratio of 3.5) into the clear sol that was prepared after mixing TNB/LA mole ratio of 5/4 with AA/TNB mole raio of 0.125. It was found that the most suitable $Li_{4/3}Ti_{5/3}O_4$ was obtained by heat treatment of xerogel at $600^{\circ}C$ for 30 hrs. The synthesized $Li_{4/3}Ti_{5/3}O_4$ showed an initial discharge capacity of 174 mAh/g and the capacity loss of about 27.3% during 25 cycles in Li/1M $LiClO_4(in\;PC)/Li_{4/3}Ti_{5/3}O_4$ at current density of $0.15mA/cm^2$ and the voltage range of 0.5~3.0 V.

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Linear Low Density Polyethylene Preparation by Titanium-Based Ziegler-Natta Catalysts (티탄이 기본인 Ziegler-Natta 촉매에 의한 선형저밀도폴리에틸렌의 제조)

  • Dong-Ho Lee;Kyung-Eun Min;Cha-Ung Kim
    • Journal of the Korean Chemical Society
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    • v.31 no.1
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    • pp.110-117
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    • 1987
  • For the preparation of linear low density polyethylene (LLDPE), the copolymerization of ethylene and 1-butene was carried out with various catalysts of titanium alkoxidealkylaluminum compound in slurry phase. The effects of catalyst components, aging time, concentration of catalyst components, polymerization time and temperature on the catalytic activity and copolymer composition were examined. The properties of copolymer obtained were also considered with the correlation to the 1-butene contents. It has been found that the titanium tetra-n-butoxide-diethylaluminum chloride catalyst system was the most suitable for the production of LLDPE with higher catalytic activity, more 1-butene content and less soluble parts. The density, glass transition temperature, melting point and heat of fusion of copolymer were decreased with increasing 1-butene contents.

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Characterization of CNT/TiO2 Electrode Prepared Through Impregnation with TNB and Their Photoelectrocatalytic Properties

  • Zhang, Feng-Jun;Chen, Ming-Liang;Oh, Won-Chun
    • Environmental Engineering Research
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    • v.14 no.1
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    • pp.32-40
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    • 2009
  • In this study, we have prepared three kinds of carbon nanometer tube $CNT/TiO_{2}$ electrodes through impregnation with different concentration titanium n-butoxide (TNB) solution. The prepared electrodes were characterized with surface properties, structural crystallinity, elemental identification and photoelectrocatalytic activity. The $N_2$ adsorption data showed that the composites had decreased surface area compared with the pristine CNT. This indicated the blocking of micropores on the surface of CNT, which was further supported by observation via SEM. XRD results showed patterns for the composites and a typical single and clear anatase crystal structure. The main elements such as C, O and Ti were existed for all samples from the EDX data. The catalytic efficiency of the developed electrode was evaluated by the photoelectrodegradation of methylene blue (MB). The positive potential applied in photoelectrocatalytic (PEC) oxidation was studied. It was found that photoelectrocatalytic (PEC) decomposition of MB solution could be attributed to combination effects between $TiO_2$ photocatalytic and CNT electro-assisted. Through the comparison between photocatalytic (PC) oxidation and photoelectrocatalytic (PEC) oxidation, it was found that the PEC oxidation efficiency for MB is higher than that of PC oxidation.

Characterization of a Novel MnS-ACF/TiO2 Composite and Photocatalytic Mechanism Derived from Organic Dye Decomposition

  • Zhu, Lei;Jo, Sun-Bok;Jo, Jung-Hwan;Ye, Shu;Ullah, Kefayat;Oh, Won-Chun
    • Journal of the Korean Ceramic Society
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    • v.51 no.3
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    • pp.139-144
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    • 2014
  • Activated carbon fiber (ACF) was modified with MnS nanoparticles to prepare MnS-ACF, and it was employed for preparation of MnS-$ACF/TiO_2$ composites with titanium (IV) n-butoxide (TNB). The properties of MnS-$ACF/TiO_2$ composites were characterized by XRD, SEM, and EDX. EDX results showed the presence of C, O, and Ti as major elements and traces of the metal elements Mn and S. The photocatlytic activity was evaluated by degradation of methyl blue (MB) and methyl orange (MO) dye. The results demonstrated that as-prepared samples could effectively photodegrade MB and MO under UV irradiation. Subsequently, the decomposition of MB solution showed the combined effects of adsorptions by ACF and enhanced photocatalytic effect by $TiO_2$. Finally, the photocatalytic effect increased due to photo-induced-electron absorption effect by ACF and electron trap effect by comodified MnS nanoparticles.

Preparation of Different Fe Containing TiO2 Photocatalysts and Comparison of Their Photocatalytic Activity

  • Meng, Ze-Da;Zhang, Kan;Oh, Won-Chun
    • Korean Journal of Materials Research
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    • v.20 no.4
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    • pp.228-234
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    • 2010
  • In this paper, Fe-$TiO_2$ and Fe-fullerene/$TiO_2$ composite photocatalysts were prepared with titanium (IV) n-butoxide (TNB) by a sol-gel method. $TiO_2$, Fe-$TiO_2$ and Fe-fullerene/$TiO_2$ were characterized by scanning electron microscopy (SEM), Transmission electron microscope (TEM), specific surface area (BET), X-ray diffraction analysis (XRD) and energy dispersive X-ray spectroscopy (EDX). The photocatalytic activities were evaluated by the photocatalytic oxidation of methylene blue (MB) solution. XRD patterns of the composites showed that the photocatalyst composite contained a typical single and clear anatase phase. The surface properties shown by SEM presented a characterization of the texture on Fe-fullerene/$TiO_2$ composites and showed a homogenous composition in the particles for the titanium sources used. The EDX spectra for the elemental identification showed the presence of O, C and Ti elements. Moreover, peaks of the Fe element were observed in the Fe-$TiO_2$ and Fe-fullerene/$TiO_2$ composites. The degradation of MB solution by UV-light irradiation in the presence of photocatalyst compounds was investigated in complete darkness. The degradation of MB concentration in aqueous solution occurred via three kinds of physical phenomena: quantum efficiency of the fullerene; organo-metallic reaction of the Fe compound; and decomposition of $TiO_2$. The degradation rate of the methylene blue solution increased when using Fe-fullerene/$TiO_2$ compounds.