• Title/Summary/Keyword: Sol-gel solution

검색결과 507건 처리시간 0.028초

Spectroscopic characterization of electroluminescent ZnS:Cu,Cl phosphor coated by sol-gel process

  • Lee, You-Hui;Han, Chi-Hwan;Han, Sang-Do;Chang, Mi-Youn;Sharma, Gaytri.;Park, Youn-Bong
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
    • /
    • pp.1323-1326
    • /
    • 2005
  • The photoluminescence, electroluminescence and surface properties of ZnS:Cu,Cl phosphor coated by sol-gel process were studies. Na-silicate was used as precursor coating material. pH of solution and the concentration of Na-silicate are the important conditions to obtain the uniform coating on the phosphors. Also, the electroluminescent devices were made with Na-silicate coated phosphor. The spectroscopic characterization is performed by photospectrometer.

  • PDF

구형 철-알루미나 입자 제조 및 피셔-트롭시 반응을 위안 전처리 조건 확립 (Development of Fe/$Al_2O_3$ Composite Granules and Activation Conditions for Fischer-Tropsch Synthesis)

  • 유계상;이동준;정광덕
    • 한국수소및신에너지학회논문집
    • /
    • 제19권6호
    • /
    • pp.545-551
    • /
    • 2008
  • Fe/$Al_2O_3$ composite granules were prepared by combining sol-gel/oil drop method. The shape of granules were mainly determined by composition and concentration of aluminum precursor. The composite granule with the lowest aluminum concentration was synthesized with 0.75M boehmite solution. The prepared granules were tested as a catalyst in the plug-flow reactor for Fischer-Tropsch synthesis. Before the reaction, catalysts were activated by hydrogen reduction and synthesis gas treatment. The activation conditions and aluminum concentration have affected catalytic performance significantly.

폴리이미드/TiO2 나노복합재의 합성과 물성 연구 (A study on the Synthesis and Characterization of Polyimide/TiO2 Nanocomposite)

  • 이봉신;이중희;김인택;이명훈;나창운
    • 대한기계학회논문집A
    • /
    • 제26권12호
    • /
    • pp.2624-2630
    • /
    • 2002
  • Organic/inorganic hybrid materials have rapidly become a fascinating research field. In this study, $polyimide/TiO_2$ composites were synthesized from nano-sized anatase $TiO_2$ and two types of polyimide, that is, BPDA-PPD and PMDA-ODA. Nano-sized $TiO_2$ particles were prepared from $TiOEt_4$ solution by the sol-gel method. The synthesized PI/$TiO_2$ composites were characterized by using XRD, TGA, FT-IR, TEM, and Atomic Force Microscope(AFM). $TiO_2$ particles were dispersed well in polyimides and the mechanical and thermal stability of polyimide was improved with $TiO_2$ nano particles.

ITO 기판에 제작된 PLZT 박막의 소성온도에 따른 특성 (Annealing-temperature Dependent Characteristics of PLZT Thin Films on ITO Coated Glass)

  • 최형욱;장낙원;박창엽
    • 한국전기전자재료학회논문지
    • /
    • 제11권2호
    • /
    • pp.128-132
    • /
    • 1998
  • 2/65/35 PLZT stock solution prepared by Sol-Gel processing was spin-coated on ITO coated glass and annealed by RTA(Rapid Thermal Annealing). The crystal structure of films was reported based on the observation of crystallization process and microstructure of the film fabricated at different fabrication condition. Films were crystallized into rhombohedral structure by annealing at $750^{\circ}C$ for 5 min. As the annealing temperature increased, the size of rosette structure of the films was grown up from $2.4{\mu}m$ to $15{\mu}m$, dielectric constant was increased, coercive field was decreased 33.82 kV/cm, remnant polarization was increased to 39.84 ${\mu}C/cm^2$ and Optical transmittance was decreased.

  • PDF

Mullite-Zirconia 복합체의 소결거동 및 기계적 성질 (Sintering Behavior and Mechanical Properties of Mullite-Zirconia Composites)

  • 박상엽
    • 한국분말재료학회지
    • /
    • 제4권1호
    • /
    • pp.9-17
    • /
    • 1997
  • The mullite-zirconia composites were prepared by the pressureless sintering with addition of 10~20 vol% ZrO$_2$(TZ3Y) in the fused mullite and sol-gel mullite matrix. The densification rate of sol-gel mullite was higher than that of fused mullite, and the addition of ZrO$_2$(TZ3Y) was effective on the densification of fused mullite. The enhancement of densification and anisotropic growth of mullite in ZrO$_2$added specimen can be explained by the solid solution effect of $Zr^{+4}$ ion in mullite. Both mechanical strength and fracture toughness of mullite-zirconia composite were enhanced compared to those of mullite. The enhancement of mechanical properties is attributed to the hinderance of grain growth and the combined toughening effects of tetra-mono phase transformation and crack deflection due to the residual stress between mullite/ZrO$_2$.

  • PDF

Fractal Analysis of the Surface in Thin Film Capacitors

  • Hong, Kyung-Jin;Min, Yong-Ki;Cho, Jae-Cheol
    • KIEE International Transactions on Electrophysics and Applications
    • /
    • 제11C권2호
    • /
    • pp.18-22
    • /
    • 2001
  • The thin films of high permitivity in ferroelectric materials using a capacitor are applied to DRAMs and FRAMs. (Ba, Sr)TiO$_3$ thin as ferroelectric materials were prepared by the sol-gel method and made by spin-coating on the Pt/Sio$_2$/Si substrate at 4,000 [rpm] for 10 seconds. The structural characteristics of the surface were analyzed by fractal dimension. The thickness of BST ceramics thin films was about 260∼280 [nm]. The property of the leakage current was stable with 10-9∼10-11[A] when the applied voltage was 0∼3[V]. BST thin films ha low leakage current properties when fractal dimension was low and a coating area was high.

솔젤법으로 제조된 고활성 $TiO_2$ 광촉매에서 미세구조-물성-공정조건의 상관성 (Microstrictire-property-processing relationship in highly active $TiO_2$ photocatalysts prepared by the sol-gel method)

  • 신현기;김헌
    • 한국결정성장학회지
    • /
    • 제9권5호
    • /
    • pp.493-497
    • /
    • 1999
  • 솔젤법을 사용하여 광촉매 $TiO_2$ 분말체를 제조하였으며 제조조건으로서 R값(물/알콕사이드 몰비), 열처리 온도, 미세구조로서 결정상, 물성으로서 비표면적과 입자크기의 상관관계를 조사하였으며 기능성으로 수용액상 염료의 광표백반응에 적용하여 광분해능을 극대화하기 위한 최적조건을 결정하였다.

  • PDF

3차원 구조의 $LiMn_2O_4$ 박막전극의 제조 및 전기화학적 특성 (Fabricatoin and electrochemical property of 3-dimesional $LiMn_2O_4$ thin film)

  • 박보건;유제혁;박용준
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
    • /
    • pp.64-65
    • /
    • 2008
  • 3D microbattery에 사용할 수 있는 $LiMn_2O_4$ 3차원 박막전극을 제조하여 그 전기화학적 특성을 관찰하였다. 3차원 구조의 형성을 위하여 먼저 polystyrene(PS) microsphere를 platinum이 증착된 Si/$SiO_2$ 기판위에 dip-coating 방식으로 코팅시켜 template로 사용하였다. 그 위에 sol-gel법을 이용, 박막을 형성시킨 후 template 를 제거하는 방식으로 $LiMn_2O_4$ 3차원 박막전극을 형성하였는데 이때 solution은 Lithium acetylacetonate[$LiCH_3CO-CHCOCH_3$], Manganese(III) acetylacetonate [Mn$(CH_3COCHCOCH_3)_3$]를 source 물질로 1-butanol과 acetic acid를 solvent로 활용하여 제조하였다.

  • PDF

Preparation of Au fine particle dispersed $TiO_2$ film by sol-gel and photoreduction process

  • Hyun, Buh-Sng;Kim, Byeong-Il;Kang, Won-Ho
    • 한국결정성장학회:학술대회논문집
    • /
    • 한국결정성장학회 1998년도 PROCEEDINGS OF THE 15TH KACG TECHNICAL MEETING-PACIFIC RIM 3 SATELLITE SYMPOSIUM SESSION 4, HOTEL HYUNDAI, KYONGJU, SEPTEMBER 20-23, 1998
    • /
    • pp.103-111
    • /
    • 1998
  • Au fine particle dispersed TiO2 film was prepared on silica glass substrate by sol-gel dip and firing process. The films were fabricated from the system of titanium tetraisoproxie-EtOh-HCl_H2O-hydrogen tetrachloroaurate(III) tetrahydrate. The conditions for the formation of the clear solution and dissolving high concentration of Au compound were examined. And a photoreduction process was adopted to control the size of gold metal particles. Phase evolution of matrix TiO2 and variation of Au particle with UV irradiation were investigated by XRDA, SEM, TEM and UV-visible spectrophotometer. And the effect of CPCl(Cetylpyridinium chloride monohydrate) as a dispersion agent was evaluated.

  • PDF

Fabrication of 3-Dimensional LiMn2O4 Thin Film

  • Park, Bo-Gun;Ryu, Jea Hyeok;Choi, Won Youl;Park, Yong-Joon
    • Bulletin of the Korean Chemical Society
    • /
    • 제30권3호
    • /
    • pp.653-656
    • /
    • 2009
  • 3-Dimensionally ordered macroporous $LiMn_2O_4$ thin film was prepared by a sol-gel and dip coating method on Pt/Ti/$SiO_2$/Si substrate. An opal structure consisting of mono dispersed polystyrene beads (300 nm) was used as a template. After solution containing Mn and Li precursors was coated on the template-deposited substrate, the template and organic materials in the precursors was removed by calcination at 400 ${^{\circ}C}$. And then the 3-dimensional $LiMn_2O_4$ thin film with spinel structure was fabricated by heat treatment at 700 ${^{\circ}C}$. The structural and electrochemical property was investigated by XRD, SEM and charge-discharge cycler.