• Title/Summary/Keyword: Sol-gel hybrid

Search Result 184, Processing Time 0.029 seconds

Development of Organic-Inorganic Hybrid Dielectric for Organic Thin Film Transistors

  • Jeong, Sun-Ho;Kim, Dong-Jo;Lee, Sul;Park, Bong-Kyun;Moon, Joo-Ho
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2006.08a
    • /
    • pp.1115-1118
    • /
    • 2006
  • Using a thermally-crosslinkable organosiloxane-based organic-inorganic hybrid material, solution processable gate dielectric layer for organic thin-film transistors (OTFTs) have been fabricated. The hybrid dielectrics are synthesized by the sol-gel process, followed by the heat-treatment at $190{\bullet}\;.{\bullet}$ To investigate the electrical property of hybrid dielectric, leakage current behavior and capacitance were measured. To fabricate coplanar-type OTFTs, Au/Cr electrode was deposited onto the heavily doped silicon substrate with the organic-inorganic hybrid dielectric layer and then ${\alpha},{\omega}-dihexylquaterthiophene$ was drop-cast between source and drain electrical performance of the fabricated transistor.

  • PDF

Fluorescence Spectroscopic and Atomic Force Microscopic Studies on the Microstructure of Polyimide/Silica-Titania Ternary Hybrid Composites

  • Park, Hae-Dong;Ahn, Ki-Youl;Mohammad A. Wahab;Jo, Nam-Ju;Kim, Il;Kim, Gyuhyun;Lee, Won-Ki;Ha, Chang-Sik
    • Macromolecular Research
    • /
    • v.11 no.3
    • /
    • pp.172-177
    • /
    • 2003
  • Biphenyltetracarboximide-phenylene diamine polyimide/silica-titania ternary hybrid composites were Prepared by thermal imidization and sol-gel reaction. Fluorescence spectroscopic, scanning electron microscopy, and atomic force microscopy studies revealed that the addition of small amount of titania showed profound effects on the microstructure and photophysical behaviors of polyimide/silica hybrid composites, when the content of silica-titania mixture was small or when the ratio of silica to titania in the mixture was high.

Monodisperse Micrometer-Ranged Poly(methyl methacrylate) Hybrid Particles Coated with a Uniform Silica Layer

  • Han, Seung-Jin;Shin, Kyo-Min;Suh, Kyung-Do;Ryu, Jee-Hyun
    • Macromolecular Research
    • /
    • v.16 no.5
    • /
    • pp.399-403
    • /
    • 2008
  • Monodisperse, micron-sized, hybrid particles having a core-shell structure were prepared by coating the surface of poly(methyl methacrylate)(PMMA) microspheres with silica and by copolymerizing acrylamide (AAm) to supply the hydrogen bonding effect by means of the amide groups. Tetraethoxysilane (TEOS) was then slowly dropped onto the medium under certain conditions. Because of the hydrogen bonding between the amide of the PMMA particles and the hydroxyl group of the hydrolyzed silanol, a silica shell was generated on the PMMA core particles. The morphology of the hybrid particles was investigated with transmission (TEM) and scanning (SEM) electron microscopy as a function of the medium conditions and the amount of TEOS. Improved thermal properties were observed by TGA analysis.

Fabrication and characterization of solution processable organosilane-modified colloidal titania nanoparticles and silica-titania hybrid films

  • Kang, Dong Jun;Park, Go Un;Lee, Hyeon Hwa;Ahn, Myeong Sang;Park, Hyo Yeol
    • Journal of Ceramic Processing Research
    • /
    • v.13 no.spc1
    • /
    • pp.78-81
    • /
    • 2012
  • Colloidal titania nanoparticles were synthesized by a simple sol-gel process. The obtained nanoparticles showed high crystallinity and were of the anatase type. These crystalline colloidal titania nanoparticles were organically modified using methyl- and glycidyl-grafted silanes in order to enhance their stability and solution processability. The stabilized colloidal titania nanoparticles could be dispersed homogeneously without aggregation and converted into silica-titania hybrid films with the heterogeneous Si-O-Ti bonds by a low-temperature solution process. The fabricated silica-titania hybrid films showed high transparency (~ 90%) in the visible range, and low RMS roughness (<1 nm). Therefore, the organosilane-modified crystalline colloidal titania nanoparticles can be used in solution-processable functional coatings for electro-optical devices.

PVA/Silica Hybrid Membrane Containing Sulfonic Acid Croup for Direct Methanol Fuel Cells Application (Sulfonic acid group을 갖는 PVA/Silica Hybrid막의 DMFC 응용)

  • Young Moo Lee;Dae Sik Kim;Kwang Ho Shin;Ho Bum Park;Ji Won Rhim
    • Membrane Journal
    • /
    • v.13 no.2
    • /
    • pp.101-109
    • /
    • 2003
  • In the present study, crosslinked poly(vinyl alcohol) (PVA) membranes were prepared at various crosslinking agent content using sulfosuccinic acid (SSA) containing sulfonic acid group ($SO_3H)$. To reduce methanol permeability, silica was introduced to the membrane using sol-gel process. The hybrid membranes were studied in relation to proton conductivity and methanol permeability. It was found that both these properties were very dependent on the effect of SSA content as a crosslinking agent and as a donor of hydrophilic $SO_3H)$ group. The proton conductivities of these PVA/SSA/Silica membranes are in the range from $10^{-3}\;to\;10^{-2}$S/cm and the methanol permeabilities are in the range from $10^{-8}\;to\;10^{-7}\;cm^2/sec$.

Preparation of Hydrophobic Antimicrobal Compounds Encapsulated Nanoparticles Using Alkoxysilane-functionalized Amphiphilic Polymer Precursor and Their Antimicrobial Properties (실란 기능화 양친성 고분자 전구체를 이용한 소수성 항균물질 담지 나노 입자 제조 및 항균 특성)

  • Kim, Nahae;Kim, Juyoung
    • Journal of Adhesion and Interface
    • /
    • v.18 no.1
    • /
    • pp.13-24
    • /
    • 2017
  • In this study, nanoparticles which encapsulated hydrophobic antimicrobial compounds with 50wt% of payload and 70%of solid content were prepared. These nanoparticles could be dispersed at water as well as various medium. Water dispersible organic-inorganic (O-I) hybrid nanoparticles were first prepared using alkoxysilane-functionalized amphiphilic polymer precursors through a conventional sol-gel process. Hydrophobic antimicrobial compound, Eugenol encapsulated nanoparticles were prepared using these O-I hybrid nanoparticles through a new nanoprecipitation process. The effect of various preparation on the size of nanoparticles, amount of payload, antimicrobial activity, and release rate of encapsulated compounds was investigated. All eugenol-encapsulated O-I nanoparticles regardless of preparation condition showed the same minimal inhibitory concentration (MIC) (50mg/ml) and 99% of antimicrobial activity for every strain. Their antimicrobial activity could maintain longer than two weeks. Especially, eugenol-encapsulated O-I nanoparticles prepared using tetraethoxysilane (TEOS) exhibited the highest payload (50wt%) and the lowest release rate which was owing to higher inorganic content in the O-I nanoparticles. And these O-I nanoparticles dispersed in hexanediol (HD) showed the highest antimicrobial activity and solid content (70wt%) because HD acted as a solvent as well as a antimicrobial agent.

Preparation and Characterization of Hard Coating Materials Based on Silane Modified Boehmite Hybrid Materials (Bohemite 나노졸을 이용한 내구성 코팅재료의 제조와 특성에 관한 연구)

  • Jeon, Seong Je;Kim, Woong;Lee, Jai Joon;Koo, Sang Man
    • Applied Chemistry for Engineering
    • /
    • v.17 no.6
    • /
    • pp.580-585
    • /
    • 2006
  • UV-thermal dually curable coating materials were prepared by the sol-gel method. Nano-sized colloidal boehmite was treated with various organo silane coupling agents. These materials could be well dispersed in various alcohols and relatively polar organic solvents such as tetrahydrofuran and acetonitrile. The coating films were prepared by a spin coating method on various substrates, which were characterized by FT-IR, Si/Al CP MAS NMR spectra, UV-Vis spectrophotometer, FE-SEM, Taber abraser, haze meter, and pencil hardness tester. The effects of molar ratio and types of silane coupling agents, curing method and ion-shower treatment were investigated. Dually curable coating method offered an optimally good quality film in both hardness and transmittance. The transparency and the hardness of the prepared films were increased with amounts of 3-(trimethoxysilyl)propylmethacrylate, and (3-glycidyloxypropyl)trimethoxysilane, respectively. The adhesion between coated layer and substrate could be enhanced by ion-shower treatment.

SPAES/Silicate Hybrid Membranes for High-Temperature and Low-Humidity Proton Exchange Membrane Fuel Cells (고온-저습용 연료전지를 위한 SPAES/Silicate 복합막)

  • So, Soon Yong;Kim, Tae Ho;Kim, Sung Chul;Hong, Young Taik
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2010.06a
    • /
    • pp.147-147
    • /
    • 2010
  • An electrolyte membranes for high temperature/low humidity is a demand for the proton exchange membrane fuel cells (PEMFCs). In this work, we prepared hybrid membranes, which have novel glass content in the hydrophilic and hydrophobic part of sulfonated poly(arylene ether sulfone) (SPAES) by in-situ sol-gel synthesis of various functional silane. The effect of silicate from functional silane content on the proton conductivity, water uptake of the hybrid membranes under high temperature and low humidity was quantitatively identified. The silicate content contributed to the enhancement of not only proton conductivity, but also water retention ability for PEMFCs operation.

  • PDF

ORGANIC - INORGANIC COMPOSITE MEMBRANE FOR POLYMER ELECTROLYTE MEMBRANE FUEL CELL

  • Shul, Yong-Gun;Kim, Hyun-Jong;Ahn, Ji-Eun;Han, Hak-Soo
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 2003.07a
    • /
    • pp.37-40
    • /
    • 2003
  • Mesoporous zeolite - heteropolyacid-polymer hybrid membrane was prepared by sol-gel processes to make a proton conducting membrane. The crystallinity of mesoporous zeolite in composite membrane was increased with contents of heteropolyacid. Proton conductivity obtained from impedance measurements increases with contents of heteropolyacid, about 10$^{-3}$ S/cm in ca. 1.5 Wt% heteropolyacid.

  • PDF