스퍼터링 방법을 이용한 금속산화물 첨가 TiO₂ 박막 제조 및 광촉매 활성

안호근 ( Ho-geun Ahn ),이도진 ( Do-jin Lee ),김기중 ( Ki-joong Kim ),김용화 ( Yong-hwa Kim ),정운조 ( Woon-jo Jeong ),문장수 ( Jang-soo Moon ) 한국환경기술학회 2007 한국환경기술학회지 Vol.8 No.2

TiO₂ 분말에 소량의 금속산화물을 습식법으로 첨가하여 타겟을 제조하고, 스퍼터링(sputtering) 방법으로 박막을 제조하여 박막의 구조적, 광학적 특성과 에틸렌 분해에 대한 광촉매 활성을 조사하였다. 제조한 금속산화물 첨가 TiO₂ 박막 밴드갭은 TiO₂ 박막보다 약간 높게 나타났다. 제조한 박막의 표면과 단면형상의 SEM과 AFM 조사에서 균일한 박막의 성장을 확인할 수 있었고, 금속산화물 첨가 TiO₂ 박막의 에틸렌에 대한 광분해 활성은 반응시간의 경과에 따라 증가하였다. Cr/TiO₂과 Mn/TiO₂ 박막의 활성은 TiO₂만의 박막보다 높았으나, Fe/TiO₂, Ni/TiO₂과 Mo/TiO₂ 박막의 경우는 분해성능이 TiO₂만의 박막보다 낮았다. 결과적으로, 습식법으로 소량의 금속산화물을 첨가한 분말을 이용하여 타겟을 제조하면, 균일한 금속산화물 첨가 TiO₂ 박막이 형성되고 에틸렌 분해에 대한 광분해 활성이 높아지는 경향이 나타나 광촉매제로 활용할 수 있음을 알았다. A small amount of metal oxides was added to TiO₂ powder by wet method, and thin film on substrate was prepared using their target by magnetron sputtering, respectively. Structural and optical properties and photocatalytic activity of the thin films were investigated. Band gap for the thin film of metal oxides added TiO₂ was a little higher than that of only TiO₂. Growth of homogeneous thin film on Al₂O₃ substrate was confirmed from SEM and AFM images for surface and cross-section of the thin films. Photocatalytic activity of ethylene over thin film of metal oxides added TiO₂ was increased with increase of reaction time. The activity for thin film of Cr/TiO₂ and Mn/TiO₂ was higher than that of only TiO₂, but the result over Fe/TiO₂, Ni/TiO₂ and Mo/TiO₂ was reverse. As a result, when the target was prepared using the metal oxides added TiO₂ powder by wet method, thin film prepared with the target was homogeneously coated on substrate, and was highly active photocatalytically.

나노 TiO₂를 적용한 식품 포장 필름 개발 및 콩나물의 이취 제거

최연욱(Yeonwook Choi),전규배(Kyu Bae Jeon),송기현(Kihyeon Song),김재능(Jai Neung Kim) 한국식품과학회 2015 한국식품과학회지 Vol.47 No.6

나노 TiO₂ 코팅 필름은 식품 포장재에서 많이 사용하는 PU와 PVB-cellulose 두 가지 바인더에 나노 콜로이달 TiO₂를 각각 3%와 5%의 농도로 혼합제조하여 OPP 필름에 코팅하였다. PVB 바인더로 코팅한 필름이 PU 바인더(3%와 5%)보다 불균일하게 필름에 코팅이 되었다. 그러나 청변현상 방지 실험과 광분해 실험에서는 필름 코팅 상태와 상관없이 선도 유지 효과가 나타났다. MB를 사용한 광분해성 효과 측정 실험에서 나노 TiO₂의 광촉매 반응으로 인해 초기 30분부터 MB가 분해되는 것을 확인하였고, 콩나물 포장재 내에서 혐기성 호흡으로 발생하는 이취인 acetaldehyde는 나노 TiO₂ 코팅 필름이 대조구에 비해 농도가 감소하는 것을 확인하였다. 따라서 개발된 나노 TiO₂ 코팅 필름으로 콩나물의 청변 현상과 이취 제거로 인해 콩나물의 보관 수명을 연장할 수 있었다. For testing the ultraviolet (UV)-blocking property of functional films coated with Nano-TiO₂ particles, UV-Vis spectra of oriented polypropylene (OPP) films uncoated and coated with TiO₂ of 3% and 5% in Polyurethane (PU) and polyvinyl butyral (PVB)-Cellulose binders were measured. The result of UV-Vis analyses showed that the film coated with 5% TiO₂ in PVB binders had a significant effect on UV protection of 90% compared with the film uncoated. Also The result of The photodegradation of methylene blue (MB), OPP films coated with 5% in both PU and PVB binders had a high photocatalytic activity for MB degradation. To evaluate the effect of the developed functional film coated with Nano-TiO₂ particles, fresh soybean sprouts were used. Nano-TiO₂ coated film was observed to decompose the off-flavor produced by soybean sprouts within packages during distribution, but uncoated film did not. Therefore, Nano-TiO₂ coated film package could give the greatest effect in extending the shelf life of soybean sprouts.

Sol-gel 법에 의해 $SnO_2$계 박막위에 코팅된 $TiO_2$ 박막의 특성

임태영,조혜미,김진호,황종희,황혜진,Lim, Tae-Young,Cho, Hye-Mi,Kim, Jin-Ho,Hwang, Jong-Hee,Hwang, Hae-Jin 한국결정성장학회 2009 한국결정성장학회지 Vol.19 No.5

Sol-gel법에 의해 친수성 투명 $TiO_2$ 박막이 제조되었고, 박막의 접촉각, 표면구조, 투과율의 특성이 측정되었다. 더욱이 박막의 친수 특성을 향상시키기 위하여 계면활성제 tween 80이 이용되었다. Tween 80의 첨가량이 0, 10, 30, 50wt%일 때, 제조된 박막의 접촉각은 각각 $41.4^{\circ}$, $18.2^{\circ}$, $16.0^{\circ}$, $13.2^{\circ}$로 확인되었다. 제조된 $TiO_2$ 박막은 자외선 조사 후 Methylene blue용액을 분해시켜 흡광도를 감소시키는 광촉매 특성을 보여주었다. 일반유리(bare glass), Antimony Tin Oxide(ATO)코팅 유리, Fluorine Tin Oxide(FTO)코팅유리, Indium Tin Oxide(ITO)코팅유리 기판 위 에 Tween 80을 30 wt% 함유한 $TiO_2$ 용액을 적층하여 박막의 접촉각과 투과율을 측정하였다. 다양한 기판에 제조된 박막은 $16.2\sim27.1^{\circ}$의 표면 접촉각을 나타냈으며 자외선 조사 후에는 접촉각이 $13.2\sim17.6^{\circ}$로 낮아졌다. 특히 ATO코팅유리와 FTO 코팅유리 기판 위에 코팅된 필름은 가시광선 영역에서 각각 74.6%, 76.8%의 높은 투과율을 나타내었고, 적외선 영역에서는 각각 54.2%, 40.4%의 낮은 투과율을 나타냈다. Hydrophilic and transparent $TiO_2$ thin film was fabricated by sol-gel method and the properties of contact angle, surface morphology, and transmittance were measured. In addition, surfactant Tween 80 was used for increasing the hydrophilic property of thin film. When the contents of Tween 80 in $TiO_2$ solution was 0, 10, 30, 50wt%, the contact angles of $TiO_2$ thin film were $41.4^{\circ}$, $18.2^{\circ}$, $16.0^{\circ}$, $13.2^{\circ}$, respectively. Fabricated $TiO_2$ thin film showed the photocatalytic property that decomposed methylene blue and decreased the absorbance of solution after UV irradiation. $TiO_2$ thin films fabricated with the solution of 30 wt% Tween 80 were deposited on glass (bare), antimony tin oxide (ATO), fluorine tin oxide (FTO), indium tin oxide (ITO) coated glass substrates, and the contact angle and transmittance of thin film was measured. The contact angles of thin films deposited on four substrates were $16.2\sim27.1^{\circ}$ and was decreased to the range of $13.2\sim17.6^{\circ}$ after UV irradiation, Especially, the thin films coated on ATO and FTO glass substrate showed high transmittance of 74.6% in visible range, respectively, and low transmittance of 54.2% and 40.4% in infrared range, respectively.

Preparationand Characterization of Rutile-anatase Hybrid TiO₂ Thin Film by Hydrothermal Synthesis

Soon Jin Kwon,Hoon Sub Song,Hyo Been Im,Jung Eun Nam,Jin Kyu Kang,Taek Sung Hwang,Kwang Bok Yi 한국청정기술학회 2014 청정기술 Vol.20 No.3

Effect of Film Thickness on the Photocatalytic Performance of TiO2 Film Fabricated by Room Temperature Powder Spray in Vacuum Process

김근영,류정호,한병동,최종진,윤운하,이병국,박동수,박찬 한국세라믹학회 2008 한국세라믹학회지 Vol.45 No.12

TiO2 is an environment-friendly semiconducting material, and it has a strong photocatalytic activity and hydrophilic effect. There are a lot of reports on the photocatalytic characteristics of TiO2, such as organic pollutants resolving, anti-bacterial, and self-purification material. In this paper, TiO2 micron-sized powders were deposited on the glass by room temperature powder spray in vacuum process, so called aerosol deposition (AD), and nano-grained TiO2 photocatalytic thin films were fabricated. The thickness of the films were controlled by changing the number of deposition cycle. Morphologies and characteristics of the AD-TiO2 thin films were examined by SEM, TEM, XRD, and UV-Visible Spectrophotometer. As the thickness of TiO2 films increased, surface roughness increased. By this increment, the reaction area between film and pollutant was enlarged, resulting in better photocatalytic property. TiO2 is an environment-friendly semiconducting material, and it has a strong photocatalytic activity and hydrophilic effect. There are a lot of reports on the photocatalytic characteristics of TiO2, such as organic pollutants resolving, anti-bacterial, and self-purification material. In this paper, TiO2 micron-sized powders were deposited on the glass by room temperature powder spray in vacuum process, so called aerosol deposition (AD), and nano-grained TiO2 photocatalytic thin films were fabricated. The thickness of the films were controlled by changing the number of deposition cycle. Morphologies and characteristics of the AD-TiO2 thin films were examined by SEM, TEM, XRD, and UV-Visible Spectrophotometer. As the thickness of TiO2 films increased, surface roughness increased. By this increment, the reaction area between film and pollutant was enlarged, resulting in better photocatalytic property.

TiO₂ (bottom)/Fe-TiO₂ (top) 이중 층 필름 위에서 CO₂ 광 환원에 의한 효과적인 메탄 제조

도정연,강미숙,임영환,곽병섭,김주용 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.1

In this study, TiO₂ and x mol. % Fe-doped TiO₂ were prepared using a conventional solvothermal method, and the prepared powders were fabricated as TiO₂/Fe-TiO₂ double-layered films for applications to the photoreduction of CO₂. The amount of CH₄ generated from the photoreduction of CO₂ with H₂O increased remarkably over the TiO₂/Fe-TiO₂ films compared to the TiO₂/TiO₂ film. In particular, the amount of CH₄ gas evolved over the TiO₂/1.0 mol. % Fe-TiO₂ film was 7 times higher than that produced over the TiO₂/TiO₂ film. A proposed model suggested that the photoactivity over the TiO₂/Fe-TiO₂ films can be enhanced by the effective charge separation and inhibited recombination of photogenerated electron-hole (e-/h+) pairs on interfacial transfer between TiO₂ and Fe-TiO₂.

PVA/AA계 광 고분자 필름의 SeO₂ 및 TiO₂ 나노 입자 첨가에 의한 회절 효율 변화

조지훈,이주철,윤성,남승웅,김대흠,Joe, Ji-Hun,Lee, Ju-Chul,Yoon, Sung,Nam, Seung-Woong,Kim, Dae-Heum 한국광학회 2010 한국광학회지 Vol.21 No.2

광고분자 필름은 광 정보를 보유한 홀로그램을 3차원적으로 저장하는 기록매질이다. 광고분자는 다른 기록 매질에 비해 높은 회절효율을 가지며, 가격이 저렴하고, 처리가 간편하다는 장점을 가지고 있어 그 활용가치가 다른 매질들에 비하여 높이 평가되고 있다. 본 연구에서는 회절특성을 갖는 $SeO_2$및 $TiO_2$를 첨가한 PVA/AA계 광 고분자 필름을 제조하였다. PVA 분자량 및 모노머와 개시제, 광 감각제의 조성은 이전 실험에 의한 최적 비율로 정하였고, $TiO_2$가 회절 효율에 직접적으로 어떤 영향을 미치는지 알아보기 위해서 $SeO_2$와 $TiO_2$의 조성을 변화시켜 가면서 실험해 보았다. $TiO_2$(0.1 mg~1.0 mg)만 첨가한 실험은 $TiO_2$의 조성이 변하여도 회절 효율의 값은 변화가 없었다. 즉, 회절 효율 변화에 직접적으로 영향을 미치지 않았다. $SeO_2$ 0.1 mg과 $TiO_2$ 0.9 mg부터 $SeO_2$ 0.9 mg과 $TiO_2$ 0.1 mg까지 조성을 변화시키면서 회절 효율을 관찰한 결과 $SeO_2$ 0.8 mg과 $TiO_2$ 0.2 mg을 넣었을 때에 가장 높은 회절효율 값인 73.75% 를 얻었다. 또한, $TiO_2$의 양에는 상관없이 $SeO_2$의 양이 증가 할수록 회절효율의 값이 완만하게 증가하는 경향을 볼 수 있었다. 과다한 양의 나노 입자를 첨가할 경우 필름 제조 시 용해도 저하에 의해 석출되어 투명한 필름을 얻을 수 없고 이는 광 특성 저하에 영향을 미치게 된다. 따라서 $TiO_2$의 함량은 효과를 나타낼 수 있는 필요한 만큼만 첨가 시켜주고 $SeO_2$의 양을 최대한 첨가 시켜주어 넓은 각도범위에서 높은 회절 효율 값을 유지할 수 있는 필름을 제작 할 수 있었다. Photopolymer is a material for recording three dimensional holograms containing photo information. Photopolymer has been found to be a proper material due to many advantages such as high DE value, easy processing, and low price. Compositions of PVA, monomer, initiater and photosensitizer were determined by previous experiments and the compositions of $SeO_2$ and $TiO_2$ were considered as variable to find out the effects of $TiO_2$ on DE. The DE values were constant for the varying compositions of $TiO_2$ (0.1 mg~1.0 mg). In other words, $TiO_2$ is not directly effective on the DE values. Composition change experiments from $SeO_2$ 0.1 mg, $TiO_2$ 0.9 mg to $SeO_2$ 0.9 mg, $TiO_2$ 0.1 showed a maximum DE value of 73.75% at a component of $SeO_2$ 0.8 mg, $TiO_2$ 0.2 mg. It seemed that regardless of the amount of $TiO_2$, increasing the amount of $SeO_2$ gently increases DE`s. If nano particles are heavily added, transparent films could not be made due to the separation of particles by the solubility decrease. Photopolymer films could be made with high DE values for an extensive angle range if $TiO_2$ additions were kept minimum and $SeO_2$ additions were kept maximum.

에어로졸 증착법을 이용한 광촉매 TiO₂ 박막 제조 및 박막의 여과 특성

최원열(Choi Wonyoul),이진우(Lee Jinwoo),김시준(Kim Shijun),김종오(Kim Jongoh) 한국지반환경공학회 2010 한국지반환경공학회논문집 Vol.11 No.1

본 연구에서는 에어로졸 증착법을 사용하여 광촉매 TiO₂ 박막을 제조하기 위하여 원심분리기의 회전속도, vibration milling 시간에 의한 입경 변화 등과 같은 운전인자의 영향을 검토하였고, 제조된 고정화 TiO₂ 광촉매 박막의 경우와 TiO₂ 광촉매 분말을 부유 상태로 존재시킨 경우와의 막투과 특성의 변화를 실험적으로 비교검토 하였다. 원심분리기의 회전속도 1000-3000rpm 에서 얻어진 TiO₂ 분말은 저온 분사 성형법(aerosol deposition, AD)으로 TiO₂ 박막을 제조하는데 있어서 nozzle powder 막힘 현상과 같은 문제점을 나타내었다. 한편, vibrating milling에 의해 제어된 TiO₂ 분말의 평균입경 크기는 vibrating milling 2시간 후 약 420㎚로 AD법을 이용한 입자의 증착에 효과적인 것으로 나타났다. XRD 분석 결과, 광촉매에 효과적인 아나타제 상을 잘 유지하고 있는 것으로 나타났으며, 이러한 결과로부터 vibrating milling은 TiO₂ 분말을 제어하는데 있어 적절한 전처리 공정임을 확인할 수 있었다. 제조된 TiO₂ 박막의 여과 특성으로 TiO₂ 분말을 분리막의 표면에 고정화 한 경우가 부유 상태일 경우보다 더 높은 막투과 유속을 나타내었다. The objective of this study is to evaluate the effect of operational parameters such as rotation speed and vibrating milling time for the fabrication of photocatalytic TiO₂ thin film using aerosol deposition methods. TiO₂ powders produced in the range of 1,000-3,000 rpm of rotation speed of centrifugal separator are ineffective on the fabrication of TiO₂ thin film by aerosol deposition due to the problem of nozzle powder jam. TiO₂ powders controlled by vibrating milling had about 420 ㎚ of average diameter after 2 hr of vibrating milling time. The result of XRD analysis indicated that TiO₂ powders had a anatase phase. Vibrating milling methods was considered to be an effective pre-treatment process for TiO₂ powder control. Consequently TiO₂ photocatalytic thin film with dispersion of anatase crystallites controled by vibrating milling was successfully fabricated by aerosol deposition. The permeation flux of TiO₂ photocatalytic thin film with the immobilized TiO₂ powder was higher than that of suspended TiO₂ powder. Therefore, TiO₂ photocatalytic thin film promises to be one of the effective methods for enhancing filtration performance for the treatment of organic pollutants.

메칠멜캅탄 가스센서용 TiO₂/전해질폴리머 박막 제조

김진호,황종희,이미재,김세기,임태영,Kim, Jin-Ho,Hwang, Jong-Hee,Lee, Mi-Jai,Kim, Sei-Ki,Lim, Tae-Young 한국결정성장학회 2010 韓國結晶成長學會誌 Vol.20 No.5

메칠멜캅탄($CH_3SH$) 가스를 검출하는 수정진동자(QCM) 가스센서를 QCM의 전극에 $TiO_2$ 나노입자와 전해질 폴리머를 증착하여 제조하였다. LBL-SA법에 의해 제조된 $TiO_2$/PSS 박막은 높은 비표면적을 나타내었고, 가스센서의 감도를 증가시켰다. 1.0 ppm의 농도를 갖는 메칠멜캅탄에 노출된 TEA 혹은 $TiO_2$/PSS 막이 증착된 QCM의 주파수 변이는 각각 약 9 Hz, 2 Hz 였다. ($TiO_2$/PSS) 박막의 증착수가 늘어남에 따라 제조된 박막의 비표면적이 증가하게 되어 QCM 센서의 주파수 변이도 점차적으로 증가하였다. 추가적으로 메칠멜캅탄 가스의 농도가 0.5 ppm에서 2.0 ppm으로 높아짐에 따라 QCM 센서의 주파수 변화도 증가되었다. 본 연구에서는, ($TiO_2$/PSS) 박막이 증착된 QCM 센서의 표면구조의 변화와 센서 특성을 측정하였다. Quartz crystal microbalance (QCM) gas sensor to detect methyl mercaptan ($CH_3SH$) gas was fabricated by depositing $TiO_2$ nanoparticles and polyelectrolyte on the electrode of QCM. The $TiO_2$/poly(sodium 4-styrenesulfonate) (PSS) thin film fabricated by a layer-by-layer self-assembly (LBL-SA) method showed a high surface area and increased the sensitivity of gas sensor. When the QCM sensors coated with triethanolamine (TEA) or ($TiO_2$/PSS) were exposed to methyl mercaptan gas (1.0 ppm), the frequency shifts of QCM with TEA casting film and $TiO_2$/PSS thin film were ca. 9 Hz and ca. 24 Hz, respectively. As the bilayer number of ($TiO_2$/PSS) increased, the frequency shift of QCM sensor with ($TiO_2$/PSS) thin film was gradually increased. In addition, the frequency shift of QCM sensor was gradually increased as the concentration of methyl mercaptan gas increased from 0.5 ppm to 2.0 ppm. In this study, the surface morphology and sensor property of QCM sensor coated with ($TiO_2$/PSS) thin film were measured.

Preparation of porous carbon-doped TiO_2 film by sol–gel method and its application for the removal of gaseous toluene in the optical fiber reactor

Moon-Sun Kim,김병우,Gang Liu,Woo Kyoung Nam 한국공업화학회 2011 Journal of Industrial and Engineering Chemistry Vol.17 No.2

In this paper, we prepared the carbon-doped TiO2 (C-TiO_2) film to enhance photodegradation efficiency (PE) of gaseous toluene under UV light. PE was affected by thickness of TiO_2 film, specific surface area of TiO_2, and carbon content doped on TiO_2. The highest value of PE was 76% with 3.2-mm-thick film. By adding 0.435 g HPC, themaximum specific surface area of TiO2 was 230 m^2 g^(-1) and PE with porous TiO_2film was 85–87% in 30 min. The specific surface area of conventional TiO_2 was 55 m^2 g^(-1) and PE with normal TiO2 film was 77–79%. To increase higher photodegradation capability of TiO2 under UV light,carbon was doped on TiO_2 by sol–gel and combustion method. PE of gaseous toluene with porous carbon-doped TiO_2 was 91–94% in 30 min and this was more enhanced by 18–19% than that with conventional TiO_2. By-products derived from the photocatalytic oxidation of toluene were mostly amyl formate and ethyl formate, which are non-toxic.