• Title/Summary/Keyword: nanosized

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The Effect of Additives on the Preparation of Nanosized TiO2 Particles (나노크기 TiO2의 제조에 미치는 첨가제 영향)

  • Kim, Seok-Hyeon;Na, Seok-En;Kim, Si-Young;Kim, Seong-Soo;Ju, Chang-Sik
    • Korean Chemical Engineering Research
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    • v.51 no.4
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    • pp.426-431
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    • 2013

  • Nanosized $TiO_2$ particles were prepared from titanium (IV) sulfate solution using base solutions at low reaction temperature ($95^{\circ}C$) and atmospheric pressure by hydrothermal precipitation method without calcination. The effects of preparation conditions, such as kind of base solutions (NaOH, $NH_4OH$, Monoethanolamine, Diethanolamine, Triethanolamine) and surfactants (CTAB, Span 20, SDBS), concentration of surfactants, temperature and pH, on the physical properties of $TiO_2$ particles have been investigated by XRD, SEM and Zeta-potential meter. Absorption area was also investigated by DRS in order to confirm the photocatalytic activity of the nanosized $TiO_2$ particles. It was turned out that, among base solutions, NaOH provides the smallest $TiO_2$ particles with excellent crystallinity. And cationic surfactant (CTAB) prepared smaller $TiO_2$ particles than any other surfactants. When CTAB is added in the concentration ratio of $Ti(SO_4)_2$:CTAB=10:1, $TiO_2$ particles with particle diameter of 5.8 nm were prepared. This is approximately 1/10 of that prepared without CTAB.

  • https://doi.org/10.9713/kcer.2013.51.4.426 인용 PDF KSCI

Effects of Calcination Temperature on Ti02 Photocatalytic Activities (TiO2 광촉매 활성에서 소성온도의 영향)

  • Kim Seung-Min;Yun Tae-Kwan;Hong Dae-Ii
    • Journal of Environmental Science International
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    • v.14 no.9
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    • pp.889-896
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    • 2005

  • The nanosized $TiO_2$ photocatalysts were prepared by the hydrolysis of $TiCl_4$ and calcined at different temperatures. The resulting materials were characterized by TGA, DSC, XRD, and TEM testing techniques. XRD, TEM, and BET measurements indicated that the particle size of $TiO_2$ was increased with rise of calcination temperature and surface area was decreased with rise of it. The prepared $TiO_2$ photocatalysts were used for the photocatalytic degradation of congo red. The effects of calcination temperature, $TiO_2$ loading, the initial concentration of congo red, and usage frequencies were investigated and the rate constants were determined by regressing the experimental data. Calcination is an effective treatment to increase the photo activity of nanosized $TiO_2$ photocatalysts resulting from the improvement of crystallinity. The optimum calcination temperature of the catalyst for the efficient degradation of congo red was found to be $400^{\cric}C$. The rate constant was decreased with increase in the initial concentration of congo red and increased with increase in the $TiO_2$ loading. In the case of $TiO_2$ photocatalysts, the photocatalytic activity wasn't greatly affected by the usage frequencies.

  • https://doi.org/10.5322/JES.2005.14.9.889 인용 PDF KSCI