• 제목/요약/키워드: photocatalytic properties

검색결과 274건 처리시간 0.025초

산소플라즈마와 급속열처리에 의해 제조된 티타니아 박막의 휴믹산 제거 (Removal of Humic Acid Using Titania Film with Oxygen Plasma and Rapid Thermal Annealing)

  • 장준원;박재우
    • 한국지하수토양환경학회지:지하수토양환경
    • /
    • 제12권3호
    • /
    • pp.29-35
    • /
    • 2007
  • 본 연구에서는 산소플라즈마로 티타늄을 산화하고 급속열처리하여 티타니아 광촉매 박막을 제조하고 휴믹산 제거실험을 수행하였다. 플라즈마 화학기상증착장치에서의 산소플라즈마는 티타늄 표면을 산화시킴으로써 광촉매 피막을 생성하게 된다. 증착조건에서 RF power는 최대 500 W 이하에서 100 W, 150 W, 300 W, 처리시간은 5분, 10분에서 조절되었다. 박막의 특성은 XPS와 XRD로 측정하였다. 실험으로서 우리는 박막이 높은 성능을 나타내는 최적을 조건을 찾았다. 또한 제조된 박막의 경우 기존 Thermal spray Titania film에 비해 2배정도 우수하였고 분말만큼 광촉매 성능을 갖는다.

화염분무열분해법을 이용한 TiO2:Fe,V 나노분말의 제조 및 VOCs 분해 특성 (Preparation of TiO2:Fe,V nanoparticles by flame spray pyrolysis and photocatalytic degradation of VOCs)

  • 장한권;장희동;김태오;김선경;최진훈
    • 한국입자에어로졸학회지
    • /
    • 제5권1호
    • /
    • pp.1-7
    • /
    • 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.

  • PDF

태양광 수소 생산용 CdS와 CdSe 흡착 TiO2 나노튜브 어레이 (TiO2 Nanotube Arrays Sensitized with CdS and CdSe for Solar Hydrogen Production)

  • ;김현;양비룡
    • 한국세라믹학회지
    • /
    • 제49권1호
    • /
    • pp.130-133
    • /
    • 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.

Photodegradation of Volatile Organic Compound (VOC) Through Pure TiO2 and V-Doped TiO2 Coated Glasses

  • Moon, Jiyeon;Kim, Seonmin
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
    • /
    • pp.425.2-425.2
    • /
    • 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.

  • PDF

Development of photocatalytic PVA/$TiO_2$ nanofiber membrane by electrospinning and its application for Air Filtration

  • Linh, Nguyen Thuy Ba;Lee, Byong-Taek
    • 한국재료학회:학술대회논문집
    • /
    • 한국재료학회 2010년도 춘계학술발표대회
    • /
    • pp.38.1-38.1
    • /
    • 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.

  • PDF

화학적 공정을 이용한 Y2Ti2O7 분말과 후막 제조 및 특성 (Fabrication and Characterization of Y2Ti2O7 Powder and Thick Film by Chemical Processing)

  • 이원준;최연빈;배동식
    • 한국재료학회지
    • /
    • 제27권5호
    • /
    • pp.289-293
    • /
    • 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.