• Title/Summary/Keyword: Titanium dioxides ($TiO_2$)

Search Result 13, Processing Time 0.021 seconds

Synthesis of Titanium Dioxides by Microemulsion Method and Their Photocatalytic Degradation of p-Nitrophenol (마이크로에멀젼법에 의한 이산화티탄의 합성 및 p-Nitrophenol의 광촉매 분해반응)

  • Jung, Won Young;Han, Yeon Hee;Lee, Gun-Dae;Park, Seong Soo;Hong, Seong-Soo
    • Applied Chemistry for Engineering
    • /
    • v.19 no.3
    • /
    • pp.351-356
    • /
    • 2008
  • Titania nanoparticles were prepared by controlled hydrolysis of titanium tetraisopropoxide (TTIP) in water-in-oil (W/O) and microemulsion stabilized with a nonionic surfactant, N P-10 (Polyoxyethylene Nonylphenol Ether: $C_9H_{19}C_6H_4(OCH_2CH_2)_{10}OH$)). The nanosized particles prepared in W/O microemulsion were characterized by FT-IR, TEM, XRD, TGA, and DTA. In addition, the photocatalytic degradation of p-nitrophenol has been studied by using a batch reactor in the presence of UV light in order to compare the photocatalytic activity of prepared nanosized titania. The nanaosized titania particles calcined at $300{\sim}600^{\circ}C$ showed an anatase structure, but it transformed to a rutile phase above $700^{\circ}C$ of calacination temperature. With an increase of $W_o$ ratio, the crystallite size increased but photocalytic activity decreased. The titania synthesized at $W_o=5$, R = 2, and calcined at $400{\sim}500^{\circ}C$ showed the highest activity on the photocatalytic degradation of p-nitrophenol.

Synthesis of Titanium Dioxides Using Low Temperature Combustion Method and Photocatalytic Decomposition of Methylene Blue (저온연소법에 의한 이산화티탄의 합성 및 메틸렌블루의 광촉매 분해반응)

  • Baek, Seung Hee;Jung, Won Young;Lee, Gun Dae;Park, Seong Soo;Hong, Seong-Soo
    • Applied Chemistry for Engineering
    • /
    • v.20 no.3
    • /
    • pp.329-334
    • /
    • 2009
  • Yttrium ions doped $TiO_2$ particles have been prepared using a low temperature combustion method. The physical properties were investigated, together with the activity of $TiO_2$ particles as a photocatalyst for the decomposition of methylene blue. From XRD results, the major phase of all the $TiO_2$ particles prepared under basic condition was an anatase structure but a rutile peak was observed when they are prepared under acidic condition. The crystallite size of $TiO_2$ particles was decreased as the molar ratio of CA/TTIP increased. The photocatalytic activity increased with an increase of CA/TTIP molar ratio and pH in the solution. In addition, the doping of 1.0 mole% yttrium ion on the $TiO_2$ enhanced the photocatalytic activity and showed the higher activity than commercial P-25 catalyst.

Synthesis and Characterization of an Organometallic Ruthenium Complex Bearing 4-Picolinic Acid Ligands for Dye-Sensitized Solar Cells (DSSCs) (피콜리닉산 리간드를 갖는 염료감응형 태양전지용 루테늄 염료 합성과 특성분석)

  • Jung, Hye-In;An, Byeong-Kwan
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.29 no.3
    • /
    • pp.192-197
    • /
    • 2016
  • A novel heteroleptic ruthenium(II) complex bearing a 4-picolinic acid unit as anchoring ligands (trans-dithiocyanato bis(4-picolinic acid)ruthenium(II) (trans-H1)) was synthesized and its chemical structure was identified by $^1H$-NMR, FT-IR and mass spectroscopy. The optical, thermal, electrochemical and dye adsorption properties of trans-H1 dye were investigated and compared with those of the gold standard ruthenium complex, Ru(4,4'-dicarboxy-2,2'-bipyridine)$_2cis(NCS)_2$ (N3). DSSCs based on trans-H1 dyes were examined under the illumination of AM 1.5 G, $100mWcm^{-2}$ and exhibited typical photovoltaic properties with an open-circuit voltage ($V_{OC}$) of 0.46 V, a short-circuit current ($J_{SC}$) of $4.10mA{\cdot}cm^{-2}$, a fill factor (FF) of 60.4%, and a conversion efficiency (PCE) of 1.14%.