• Title, Summary, Keyword: Super Hydrophilic

Search Result 29, Processing Time 0.049 seconds

Estimation of energy self-sufficiency in municipal wastewater treatment plant using photovoltaic power simulated by azimuth and hydrophilic coating (방위각과 초친수코팅에 따른 태양광발전량 시뮬레이션과 하수처리장 에너지자립율 산정)

  • An, Young-Sub;Kim, Sung-Tae;Kang, Ji-Hoon;Chae, Kyu-Jung;Yoon, Jong-Ho
    • KIEAE Journal
    • /
    • v.11 no.6
    • /
    • pp.133-138
    • /
    • 2011
  • This paper presents energy self-sufficiency simulated in municipal wastewater treatment plants (WWTPs) by adopting solar energy production systems that were simulated by varying azimuth and super-hydrophilic coating on the surface of photovoltaic (PV). Relative to the national average energy consumption in WWTPs, the employment of 100 kW PV system was simulated to achieve 2.75% of energy self-sufficiency. The simulated results suggested that the installation of PVs toward South or Southwest would produce the highest energy self-sufficiency in WWTPs. When super-hydrophilic coating was employed in the conventional PV, 5% of additional solar energy production was achievable as compared to uncoated conventional PV. When 100 kW of PV system was installed in a future test-bed site, Kihyeung Respia WWTP located in Yongin, South Korea, the energy self-sufficiency by solar power was simulated to be 1.77%. The simulated solar power production by azimuth and super-hydrophilic coating will be useful reference for practitioners in designing the solar PV systems in the WWTPs.

Patterning of Super-hydrophobic Surface Treated Polyimide Film (초발수 기판의 친수 패터닝을 이용한 금속배선화)

  • Rha, Jong-Joo;Um, Dae-Yong;Lee, Gun-Hwan;Choi, Doo-Sun;Kim, Wan-Doo
    • Proceedings of the KSME Conference
    • /
    • /
    • pp.1553-1555
    • /
    • 2008
  • Super-hydrophobic treated Polyimide film was used as a flexible substrate for developing a new method of metallization. Hydrophilic patterns were fabricated by IN irradiation through shadow mask. Patterned super-hydrophobic substrate was dipped into a bath containing silver nano ink Silver ink was only coated on hydrophilic patterned area. Metal lines of $600{\mu}m$ pitch were fabricated successfully. However, their thickness was too thin to serve as interconnection. To overcome this problem, iterative dipping was conducted. After repeating five times, the thickness of silver metal lines were increased to over than $2{\mu}$. After heat treatment of silver lines, their resistivities were reduced to order of $30{\mu}{\Omega}$-cm the similar level of values reported in other literatures. So, a new method of metallization has high potential for application of RFID antenna and flexible electronics substrates.

  • PDF

New Field in Photoelectrochemistry: Photocatalytic, Super-hydrophilic and Super-hydrophobic Functions of $TiO_2$ Coatings

  • Fujishima Akira;Hashimoto Kazuhito
    • Journal of the Korean Electrochemical Society
    • /
    • v.3 no.2
    • /
    • pp.81-84
    • /
    • 2000
  • This article deals with various photochemical processes occurring at $TiO_2$ surface and its applications in practical living conditions. In the first part, we present an overview of $TiO_2$ photocatalysis under weak W illumination with a special emphasis on bactericidal and detoxification properties of $TiO_2$ films. The second part deals with the photoinduced super hydrophilic TiCt surftce which has a wide commercial applications. In the last part, we present our recent work on boehmite-based super hydrophobic surfaces containing small amount of $TiO_2$ to obtain self-cleaning effect.

Photocatalyst Surface Properties of the Oxide Thin Films According to the Plasma Etching Process (플라즈마 에칭공정에 따른 산화물 박막의 광촉매 표면 특성)

  • Lee, Chang-Hyun;Seo, Sung-Bo;Oh, Ji-Yong;Jin, Ik-Hyeon;Sohn, Sun-Young;Kim, Hwa-Min
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.28 no.5
    • /
    • pp.300-305
    • /
    • 2015
  • $WO_3$, $SiO_2$, and $TiO_2$ films with hydrophilic property are deposited by rf-magnetron sputtering. Their wettability is strongly depends on the presence or absence of the oxygen plasma etching on the glass substrates. The $TiO_2$ film of 50 nm-thick on the plasma etched glass shows a water contact angle (WCA) below $5^{\circ}$ which means a super-hydrophilic surface. However, WCA values are gradually degraded when the films are exposed under atmosphere, especially $WO_3$. In order to improve hydrophilic property, the degraded films can be again recovered by UV illumination for 10 sec using UV-light and the $TiO_2$ film shows a super-hydrophilic surface about $3^{\circ}$.

Super Hydrophilic Properties of SiO2-TiO2 Thin Film Prepared by Sol-Gel Method (졸-겔법에 의한 SiO2-TiO2 박막의 초친수성)

  • Park, Min-Jung;Lee, Kyoung-Seok;Kang, Jong-Bong;Mun, Chong-Soo
    • Korean Journal of Materials Research
    • /
    • v.17 no.3
    • /
    • pp.125-131
    • /
    • 2007
  • [ $TiO_{2}-solution$ ] was aaded in $SiO_{2}-solution$ by various composition. $SiO_{2}-TiO_{2}$ thin films were obtained by the dip-coating method on the $SiO_{2}$ glass substrates, and then heat-treated at various temperature. Nano-size $TiO_{2}$ particles dispersed $SiO_{2}-TiO_{2}$ films showed absorption peak by quantum size effect at short wavelength region $350{\sim}400nm$, which made them good candidates for non-linear optical materials and photo-catalytic materials. The thickness of $SiO_{2}-TiO_{2}$ films were $300{\sim}430nm$. The contact angle of $SiO_{2}-TiO_{2}$ films for water was $5.3{\sim}47.9^{\circ}$, and therefore it is clear that $SiO_{2}-TiO_{2}$ films have super hydrophilic properties and the self-cleaning effects.

Super Hydrophilic Properties of ZrO2 Thin Film Containing TiO2 Photo-Catalysis (광촉매 TiO2 함유 ZrO2 박막의 초친수성)

  • Jung, Ki-Uk;Lee, Tea-Gu;Mun, Chong-Soo
    • Korean Journal of Materials Research
    • /
    • v.18 no.4
    • /
    • pp.211-217
    • /
    • 2008
  • A $ZrO_2$ coating solution containing $ZrO_2$ photo-catalysis, which is transparent in visible light, was prepared by the hydrolysis of alkoxide, and thin films on the $SiO_2$ glass substrate were formed in a dipcoating method. These thin films were heat-treated at temperatures ranging from $250^{\circ}C-800^{\circ}C$ and their characteristics were subjected to thermal analysis, XRD, spectrometry, SEM, EDS, contact angle measurement, and AFM. Tetragonal $ZrO_2$ phase was found in the thin film heat treated at $450^{\circ}C$, and anatase $TiO_2$ phase was detected in the thin film heat-treated at $600^{\circ}C$ and above. The thickness of the films was approximately 300 nm, and the roughness was 0.66 nm. Thus, the film properties are excellent. The films are super hydrophilic with a contact angle of $4.0^{\circ}$; moreover, they have self-cleaning effect due to the photo catalytic property of anatase $TiO_2$.

Visualization of Flow and Wetting Transition in PDMS Superhydrophobic Microchannel (PDMS 기반 초소수성 마이크로 채널내의 유동 및 표면 젖음 전이 가시화에 관한 연구)

  • Kim, Ji-Hoon;Hong, Jong-In;Byun, Do-Young;Ko, Han-Seo
    • 한국전산유체공학회:학술대회논문집
    • /
    • /
    • pp.671-674
    • /
    • 2008
  • We investigate the slippage effect in a micro-channel depending on the surface characteristics; hydrophilic, hydrophobic, and super-hydrophobic wettabilities. The micro-scale grooves are fabricated on the vertical wall to make the super-hydrophobic surfaces, which enable us visualize the flow fields near walls and directly measure the slip length. Velocity profiles are measured using micro-particle image velocimetry (Micro-PIV) and compared those in the hydrophilic glass, hydrophobic PDMS, and super-hydrophobic PDMS micro-channels. To directly measure the velocity in the super-hydrophobic micro-channel, the transverse groove structures are fabricated on the vertical wall in the micro-channel. The velocity profile near the wall shows larger slip length and, if the groove structure is high and wide, the liquid meniscus forms curves into the valley so that the wavy flow is created after the grooves.

  • PDF

Hydrophilic/Hydrophobic Conversion of $TiO_2$ Films by Reactive Magnetron Sputtering (Reactive Magnetron Sputtering법으로 제조된 $TiO_2$의 친수성/소수성 변환 특성)

  • 이영철;박용환;안재환;고경현
    • Journal of the Korean Ceramic Society
    • /
    • v.36 no.11
    • /
    • pp.1211-1216
    • /
    • 1999
  • TiO2 thin films were prepared by reactive magnetron sputtering on glass substrate and subjected into investigation about their hydrophilic properties. Varing Ar/O2 ration and post annealing at 50$0^{\circ}C$ for 12h anatase and rutile phases of TiO2 films were obtained. Hydrophilic properties were evaluated by determination of contact angle of water droplet on TiO2 surface. On as-annealed TiO2 films water droplet spreaded widely with ~0$^{\circ}$contact angle. Sonication(60 Hz, 28kHz 40kHz) and following dark room treatments turned these hydrophilic TiO2 films into hydrophobic state. All of hydrophobic films were converted recersibly into their original state after UV illumination. Hydrophobic states of anatase films were saturated after sonication and remain same during dark room treatment. But it was found that the conversion into hydrophobic state of rutile films progressed. further after sonication. Therefore it was concluded that Ti3+/Ti+4 ratio is the key to determine hydrophilicity of TiO2 surface so that different surface structure of polymorphs could lead to unique characteristics.

  • PDF

Study of surface modification and contact angle by electrospun PVdF-HFP membrane with DLC coating (DLC 코팅에 의한 PVdF-HFP 막의 표면변화 및 접촉각 연구)

  • Lee, Tae Dong;Cho, Hyun;Yoon, Su Jong;Kim, Tae Gyu
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.24 no.1
    • /
    • pp.33-40
    • /
    • 2014
  • Poly vinylidene fluoride-co-hexafluoropropylene (PVdF-HFP) membrane were prepared by the electrospinning technique. We had applied a DLC coating process and then the surface of the membrane and the contact angle change was investigated. Electrospun fibrous PVdF-HFP membrane surface became to wrinkled shape by Ar plasma treatment and treatment conditions. The wrinkled surface of PVdF-HFP membrane became super-hydrophilic. However, after DLC coating process, it became super-hydrophobic. The resulting surfaces were characterized by water contact angle measurement, X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FE-SEM). Resultantly it was recognized that the wettability characteristics of the membrane surfaces depended on the chemical composition and surface morphology.