• 제목/요약/키워드: Metal Nanoparticles

검색결과 449건 처리시간 0.034초

Development of Gold Phosphorus Supported Carbon Nanocomposites

  • Mayani, Vishal J.;Mayani, Suranjana V.;Kim, Sang Wook
    • Bulletin of the Korean Chemical Society
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    • 제35권2호
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    • pp.401-406
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    • 2014
  • Metal-containing carbon nanocomposites have shown significance promise in the area of energy storage, heterogeneous catalysis and material science because of their morphology and combined properties. Phosphorus-doped carbon nanocomposites with gold nanoparticles were developed by applying a simple impregnation method and metal deposition technique. Gold-phosphorus supported carbon nanocomposites with two sized (25 and 170 nm) were prepared from economical petroleum pitch residue as the carbon source using an advanced silica template method. These nanocomposites will lead to the novel applications in the field of material science with the combined properties of gold, phosphorus and carbon. The newly prepared gold phosphorus supported carbon nanocomposites were fully characterized using a range of different physico-chemical techniques.

Theoretical Optical Waveguide Investigation of Self-Organized Polymer Thin Film Nanostructures with Nanoparticle Incorporation

  • Lau, King Hang Aaron;Knoll, Wolfgang;Kim, Dong-Ha
    • Macromolecular Research
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    • 제15권3호
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    • pp.211-215
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    • 2007
  • Hybrid thin film nanostructures composed of metal nanoparticles (NPs) and self-assembled polymer films with different spatial distributions of NPs were analyzed by optical waveguide spectroscopy (OWS). Specifically, the dielectric constants were calculated using effective medium theory for the incorporation of 1 vol% Au NP into the block copolymer (BCP) films having a cylindrical nanodomain morphology. Three cases were considered: uniform distribution of NPs in the film; selective distribution of NPs only in the cylindrical domains; and segregation of NPs to the center of the cylindrical domains. The optical waveguide spectra derived from the calculated dielectric constants demonstrate the feasibility of experimentally distinguishing the composite nanostructures with different inner morphologies in the hybrid metal NP-BCP nanostructures, by the measurement of the dielectric constants using OWS.

전계효과트랜지스터 기반 반도체 소자 응용을 위한 스프레이 공정을 이용한 nc-ZnO/ZnO 박막 제작 및 특성 분석 (Morphological and Electrical Characteristics of nc-ZnO/ZnO Thin Films Fabricated by Spray-pyrolysis for Field-effect Transistor Application)

  • 조준희
    • 반도체디스플레이기술학회지
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    • 제20권4호
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    • pp.1-5
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    • 2021
  • Field-effect transistors based on solution-processed metal oxide semiconductors has attracted huge attention due to their intrinsic characteristics of optical and electrical characteristics with benefits of simple and low-cost process. Especially, spray-pyrolysis has shown excellent device performance which compatible to vacuum-processed Field-effect transistors. However, the high annealing temperature for crystallization of MOS and narrow range of precursors has impeded the progress of the technology. Here, we demonstrated the nc-ZnO/ZnO films performed by spray-pyrolysis with incorporating ZnO nanoparticles into typical ZnO precursor. The films exhibit preserving morphological properties of poly-crystalline ZnO and enhanced electrical characteristics with potential for low-temperature processability. The influence of nanoparticles within the film was also researched for realizing ZnO films providing good quality of performance.

Zeolitic Imidazolate Framework-7로 합성한 ZnO 나노입자의 Acetone 가스 감응 특성 (Acetone Sensing Characteristics of ZnO Nanoparticles Prepared from Zeolitic Imidazolate Framework-7)

  • 윤지원;;박준식;이종흔
    • 센서학회지
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    • 제26권3호
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    • pp.204-208
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    • 2017
  • Highly uniform and well-dispersed Zeolitic Imidazolate Framework-7 (ZIF-7) particles were prepared by the precipitation of $Zn^{2+}$ using benzimidazole, which were converted into ZnO nanoparticles by heat treatment at $500^{\circ}C$ for 24 h. The ZIF-7 derived ZnO nanoparticles showed abundant mesopores, high surface area, and good dispersion. The gas sensing characteristics toward 5 ppm acetone, ethanol, trimethylamine, ammonia, p-xylene, toluene, benzene, and carbon monoxide and carbon dioxide were investigated at $350-450^{\circ}C$. ZIF-7 derived ZnO nanoparticles exhibited high response to 5 ppm acetone ($R_a/R_g=57.6$; $R_a$: resistance under exposure to the air, Rg: resistance under exposure to the gas) at $450^{\circ}C$ and negligible cross-responses to other interference gases (trimethylamine, ammonia, p-xylene, toluene, benzene, carbon monoxide, carbon dioxide) and relatively low responses to ethanol. ZIF derived synthesis of metal oxide nanoparticles can be used to design high performance acetone sensors.

전자장치 응용을 위한 금속(은, 구리) 나노입자의 합성 (Synthesis of Metal Nanoparticles for the Application of Electronic Device)

  • 전병호;조수환;조정민;김성은;김동훈;김성진
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.53-53
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    • 2010
  • The development of synthetic pathway to produce a highly yield nanoparticles is an important aspect of industrial technology. Herein, we report a simple, rapid approach to synthesize organic-soluble Cu and Ag nanoparticles in colloidal method for the application in a conductive pattern using inkjet printing. The silver nanoparticles have been synthesized in highly concentrated organic phase. The Cu nanoparticles have been synthesized by the reducing of the copper oxide materials using acid molecules in high concentrated organic phase. Their sintering and electric conductivity properties were investigated by melting process between $200^{\circ}C$ and $250^{\circ}C$ for application to printed electronics.

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Curcumin-Loaded PLGA Nanoparticles Coating onto Metal Stent by Electrophoretic Deposition Techniques

  • Nam, So-Hee;Nam, Hye-Yeong;Joo, Jae-Ryang;Baek, In-Su;Park, Jong-Sang
    • Bulletin of the Korean Chemical Society
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    • 제28권3호
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    • pp.397-402
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    • 2007
  • Restenosis after percutaneous coronary intervention (PCI) continues to be a serious problem in clinical cardiology. To solve this problem, drug eluting stents (DES) with antiproliferative agents have been developed. Variable local drug delivery systems in the context of stenting require the development of stent manufacture, drug pharmacology and coating technology. We have worked on a system that integrates electrophoretic deposition (EPD) technology with the polymeric nanoparticles in DES for local drug delivery and a controlled release system. The surface morphology and drug loading amount of DES by EPD have been investigated under different operational conditions, such as operation time, voltage and the composition of media. We prepared poly-D,L-lactide-co-glycolic acid (PLGA) nanoparticles embedded with curcumin, which was done by a modified spontaneous emulsification method and used polyacrylic acid (PAA) as a surfactant because its carboxylic group contribute negative charge to the surface of CPNPs (?53.5 ± 5.8 mV). In the process of ‘trial and error' endeavors, we found that it is easy to control the drug loading amount deposited onto the stent while keeping uniform surface morphology. Accordingly, stent coating by EPD has a wide application to the modification of DES using various kinds of nanoparticles and drugs.

기상합성공정을 이용한 FePt 나노입자의 실시간 L10 상변화 (Real-time Transformation of FePt Nanoparticles to L10 Phase by the Gas Phase Synthesis)

  • 이기우;이창우;김순길;이재성
    • 대한금속재료학회지
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    • 제49권1호
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    • pp.46-51
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    • 2011
  • Real-time formation of $L1_0$ phase of FePt nanoparticles in the gas phase during ultrasonic-spray pyrolysis is first discussed in the present study. Without any post heat treatment, $L1_0$ phase of FePt nanoparticles appeared at the temperature above $900^{\circ}C$ in the gas phase synthesis. X-ray diffractometry (XRD) and transmission electron microscopy (TEM) studies revealed that FePt nanoparticles less than 10 nm in size contained small volume of $L1_0$ fct phase. However, in other samples obtained at the temperature below $900^{\circ}C$, iron oxide phase co-existed and no evidence of phase transformation was found. Thus, it is anticipated that the time of flight of particles required for crystallization and phase transformation was extended according to the increase of the collision rate. Finally, magnetic properties represented by coercivity and saturation magnetization and functional groups on the particle surface were discussed based on VSM and FT-IR results.