http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
정충경,부진효,배인섭,S. H. Jeong,S.-J. Cho,Y.-H. Song 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.51 No.3
We have deposited titanium dioxide (TiO2) thin films on glass using a single molecular precursor such as titanium (IV) iso-propoxide (Ti[OCH(CH3)2] 4, 97 %) by sol-gel process. In order to elevate photocatalytic activity of the as-grown TiO2 films, argon and oxygen plasmas ignited by microwave (MW) discharge at 300 W under vacuum condition were also used within 5 min. at room temperature. Photocatalytic activity was evaluated by the measurements of the contact angle, FT-IR, XPS, and AFM analysis. In this work, the effect of the plasma on the improvement of hydrophilic property of TiO2 photocatalyst has mainly been investigated. Superhydrophilic property and smooth surface morphology appeared in the UV light irradiation with O2 plasma treatment more than Argon plasma treatment. Based on this work, we confirmed that the oxygen MW plasma treatment method was very reliable method for the synthesis of TiO2 thin films with high catalytic performance.
Properties of SiOxNy Thin Films Deposited with a Single Molecular Precursor by Using RF PECVD
정충경,부진효,배인섭,S.-H. Jeong,W. S. Choi 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.51 No.3
We have deposited SiOxNy thin films on both Si(100) and glass substrates by using a tetraethyl orthosilicate (TEOS) single precursor at nitrogen flow rates of 0 100 sccm by using a radiofrequency Plasma Enhanced Chemical Vapor Deposition (PECVD) method. The film growth orientation and microstructural characteristics were analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Deposition at higher nitrogen flow rates results in finer clusters with smaller grain sizes. Moreover, we used UV/Vis and FT-IR spectroscopy and ellipsometry to investigate the optical properties for various nitrogen flow ratios. As-deposited SiO2 films showed an amorphous structure, but samples annealed in an O2 ambient at 900 C showed increased crystallinity. Also, the leakage current densities of the SiO2 and the SiOxNy films annealed at 900 C in an O2 ambient were about 4.0 × 10.8 and 1.5 × 10.7 A/cm2.
대기압 플라즈마를 이용한 TiO<sub>2</sub> 광촉매의 효율향상을 위한 표면 개질 연구
조상진,정충경,김성수,부진효,Cho, S.J.,Jung, C.K.,Kim, S.S.,Boo, J.H. 한국진공학회 2010 Applied Science and Convergence Technology Vol.19 No.1
$TiO_2$의 표면의 친수성을 증가시키기 위하여 dielectric barrier discharge (DBD)에 의해 발생된 대기압 플라즈마 (atmospheric pressure plasma: APP)를 이용 RF power 50~200 W 범위에서 Ar과 $O_2$ 가스를 사용 대기압 플라즈마로 광촉매 표면을 개질하였다. Ar 가스 단독으로 처리한 시료의 접촉각은 20도에서 10도로 감소하였으며, $O_2$ 가스를 반응성 가스로 하여 처리한 경우에는 접촉각이 20도에서 1도 미만으로 감소하였다. 동일한 RF power에서 $O_2$ 플라즈마 처리 시 더 낮은 접촉각을 확인하였는데, 이는 $TiO_2$ 표면과 산소원자의 결합으로 인하여 표면의 polar force의 증가에 의한 것으로 판단되어 대기압 플라즈마로 처리된 시료의 X-ray photoelectron spectroscopy (XPS)의 스펙트럼 분석결과 OH 작용기의 증가로 표면의 친수성이 증가됨을 확인하였다. 대기압 플라즈마로 처리된 시료와 처리하지 않은 시료의 접촉각은 모두 시간이 지남에 따라 증가하지만 플라즈마 처리 된 시료의 접촉각 증가는 플라즈마 처리하지 않은 시료의 접촉각 보다 작은 것을 확인하였다. 또한, 페놀 분해 실험을 통하여 플라즈마 표면처리를 통하여 $TiO_2$ 광촉매의 분해 효율이 크게 향상되는 것을 확인하였다. To improve surface wettability, each sample was treated by atmospheric pressure plasma (APP) using dielectric barrier discharge (DBD) system. Argon and oxygen gases were used for treatment gas to modify the $TiO_2$ surface by APP with RF power range from 50 to 200 W. Water contact angle was decreased from $20^{\circ}$ to $10^{\circ}$ with argon only. However, water contact angle was decreased from $20^{\circ}$ to < $1^{\circ}$ with mixture of argon and oxygen. Water contact angle with $O_2$ plasma was lower than water contact angle with Ar plasma at the same RF power. It seems to be increasing the polar force of $TiO_2$ surface. Also, analysis result of X-ray photoelectron spectra (XPS) shows the increase of intensity of O1s shoulder peak, resulting in increasing of surface wettability by APP. Moreover, each water contact angle increased according to increase past time. However, contact angle increase with plasma treatment was lower than without plasma treatment. Additionally, the efficiency of $TiO_2$ photocatalyst was improved by plasma surface-treatment through the degradation experiment of phenol.