• 제목/요약/키워드: self-assembled multilayer films

검색결과 15건 처리시간 0.031초

Reversible Optical Information Stroage of Self-Assembled Alternating Multilayer Films: Bipolar Amphiphile-Polyelectrolyte

  • 홍종달;박응수;박애리
    • Bulletin of the Korean Chemical Society
    • /
    • 제19권11호
    • /
    • pp.1156-1160
    • /
    • 1998
  • Alternating multilayer films of a cationic bipolar amphiphile and an anionic polyelectrolyte were prepared by a self-assembly method based on electrostatic attraction between opposite charges. The bipolar amphiphile contains an azobenzene unit in order to allow for a trans-cis photoisomerization to take place. Optical birefringence or dichroism was induced in the self-assembled film upon linearly polarized light irradiation. This dichroism could be reversibly written and erased by irradiation with light of an appropriate wavelength.

Layer-by-Layer 자기조립법에 의한 Poly(ethyiene-alt-maleic anhydride)i Poly(4-vinyl pyrtdine) 다층막 제조 (Fabrication of an Alternating Multilayer Film of Poly(ethylene-alt-maleic anhydride) and Poly(4-vinyl pyridine) by Layer-by-Layer Self-Assembly Method)

  • 이준열;홍숙영
    • 폴리머
    • /
    • 제29권4호
    • /
    • pp.392-398
    • /
    • 2005
  • Layer-by-layer(LbL) 흡착에 의한 poly(ethylene-alt-m미? anhydride) (PEMAh)/poly(4-vinyl pyridine) (P4VP) 자기조립 다층박막을 제조하였다. 자기조립 다층막을 이루는 PEMAh/P4VP 두 고분자 사이의 수소 결합과 정전기적 인력이 다층막을 이루는 원동력이라는 것이 푸리에 변환 적외선(FT-IR) 분광분석에 의해서 확인되었다. 다층막의 균일한 자기조립 과정은 PEMAh/P4VP 이중층막의 적층 수 증가에 따른 UV-vis 스펙트럼의 256 nm에서 나타나는 P4VP 특성 흡수 피크의 선형적 증가에 의해서 확인할 수 있었다. 다층막을 이루는 고분자 전해질 담지 용액의 조건 변화가 다층막 형성에 미치는 영향을 살펴보기 위하여 두 고분자 용액의 농도 및 PEMAh 담지용액의 pH를 변화시키면서 다층막을 제조하였다. 다층막의 두께, 흡착된 고분자 전해질 질량 및 표면 거칠기의 변화를 UV-vis 분광 분석, 수정진동자 미량저울(quartz crystal microbalance;QCM) 및 원자 힘 현미경(atomic force microscopy;AFM)을 이용하여 측정하였다.

Self-Assembled $TiO_2$ and Polyelectrolyte Multilayer as OTFT Gate Insulator

  • Moon, Zi-Su;Kim, Hong-Doo
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
    • /
    • pp.1422-1424
    • /
    • 2009
  • Modified self-assembled $TiO_2$ and polyelectrolyte multilayer film have been used as OTFT insulator. Both films were used as gate insulator and their thickness were reduced to the order of 10nm. The operating voltage of OTFT was substantially reduced due to nanoscale thickness of titanium oxide and polyelectrolyte multilayer. Pentacene-based OTFT characteristics will be discussed.

  • PDF

Ordered Hybrid Nanomaterials from Self-Assembled Polymeric Building Blocks

  • Kim, Dong-Ha
    • 한국고분자학회:학술대회논문집
    • /
    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
    • /
    • pp.309-309
    • /
    • 2006
  • Latest developments on hybrid nanostructured materials fabricated by applying self-assembly strategies on organic/inorganic nanotemplates are discussed. Within this frame, numerous functional nanomaterials including arrays of composite metal/semiconductor nanoparticles, planar waveguides and functional multilayer thin films are generated using self-assembled polymers as templates or building blocks. In particular, surface plasmon resonance based optical sensing is employed to investigate nanofabrication processes occurring in nanoscale dimention. We also suggest unprecedented pathways to hybrid supramolecular multilayer nanoarchitectures in 1D or 2D geometry via layer-by-layer self-assembly.

  • PDF

Sonochemical Synthesis of Closed [5,6]-bridged Aziridino[70]fullerene Derivative and Self-assembled Multilayer Films

  • Yoon, Shin-Sook;Hwang, Sung-Ho;Hong, Sung-Kyu;Lee, Jeong-Ho;Ko, Weon-Bae
    • Carbon letters
    • /
    • 제10권4호
    • /
    • pp.325-328
    • /
    • 2009
  • This cycloaddition of [70]fullerene with methyl azidoacetate in benzene under ultrasonic irradiated condition afforded the closed [5,6]-bridged aziridino[70]fullerene derivative, which was unusual product of cycloaddition to the 5,6-junction of fullerene. Its structure was determined by FAB-MS, UV-vis, $^1H-$ and $^{13}C$-NMR spectral data. The closed [5,6]-bridged aziridino[70]fullerene-functionalized gold nanoparticle films were self-assembled using the layer-by-layer method on the reactive of glass slides functionalized with 3-mercaptopropyl trimethoxysilane. The functionalized glass slides were alternately soaked in the solution containing closed the [5,6]-bridged aziridino[70]fullerene and 4-aminothiophenoxide/hexanethiolate-protected gold nanoparticles. The closed [5,6]-bridged aziridino[70]fullerene-functionalized gold nanoparticle films have grown up to 5 layers depending on the immersion time. The self-assembled nanoparticle multilayer films were characterized using UV-vis spectroscopy showed that the surface plasmon band of gold at 527 nm gradually became more evident as successive layers were added to the films.

Synthesis ad Self-assembled Multilayer Film Fabrication via Layer-by-layer Deposition of Water-soluble Aromatic Polyimines

  • Lee, Taek-Seung;Kim, Jae-Hyeon;Kumar, Jayant;Tripathy, Sukant
    • 한국섬유공학회:학술대회논문집
    • /
    • 한국섬유공학회 1997년도 추계총회 및 학술발표회 논문집
    • /
    • pp.71-75
    • /
    • 1997
  • A new series of water-soluble conjugated aromatic polyimines containing sulfonate groups have been synthesized via polycondensation reaction between diamines and dialdehydes at room temperature. Self-assembled multilayer films consisting each polyimine as a polyanion and poly(diallyldimethylammonium hydrochloride) as a polycation were fabricated successfully by alternate deposition in corresponding aqueous solutions.

  • PDF

Preparation of Gold Nanoisland Arrays from Layer-by-Layer Assembled Nanoparticle Multilayer Films

  • Choi, Hyung-Y.;Guerrero, Michael S.;Aquino, Michael;Kwon, Chu-Hee;Shon, Young-Seok
    • Bulletin of the Korean Chemical Society
    • /
    • 제31권2호
    • /
    • pp.291-297
    • /
    • 2010
  • This article introduces a facile nanoparticle self-assembly/annealing method for the preparation of nanoisland films. First, nanoparticle-polymer multilayer films are prepared with layer-by-layer assembly. Nanoparticle multilayer films are then annealed at $~500^{\circ}C$ in air to evaporate organic matters from the films. During the annealing process, the nanoparticles on the solid surface undergo nucleation and coalescence, resulting in the formation of nanostructured gold island arrays. By controlling the overall thickness (number of layers) of nanoparticle multilayer films, nanoisland films with various island density and different average sizes are obtained. The surface property of gold nanoisland films is further controlled by the self-assembly of alkanethiols, which results in an increased surface hydrophobicity of the films. The structure and characteristics of these nanoisland film arrays are found to be quite comparable to those of nanoisland films prepared by vacuum evaporation method. However, this self-assembly/annealing protocol is simple and requires only common laboratory supplies and equipment for the entire preparation process.

자기조립 풀러렌$[C_{70}]$-금 나노입자 필름 제조와 초음파적, 화학적 안정성 (Ultrasonic, Chemical Stability and Preparation of Self-Assembled Fullerene$[C_{70}]$-Gold Nanoparticle Films)

  • 고원배;손영석
    • Elastomers and Composites
    • /
    • 제40권4호
    • /
    • pp.272-276
    • /
    • 2005
  • 3-aminopropyltrimethoxysilane을 처리한 반응성 있는 유리표면 위에 'dirt-ball' 방법을 사용하여 $C_{70}$-금 나노입자 다중성막 필름을 자기조립하였다. 표면처리한 유리막을 $C_{70}$${\omega}$-아미노기를 가진 금 나노입자를 포함하고 있는 용액속에 담그었다. 유기반응(아민화 반응)은 여러층으로 쌓인 다중성막 $C_{70}$-금 나노입자 필름을 용이하게 자기조립 할 수 있었다. $C_{70}$-금 나노입자 필름의 화학적 안정성은 산성용액에 필름을 담근후 흡수도의 변화를 측정함으로 조사되었다. 또한 나노입자 필름의 초음파적 안정성은 초음파 조건에 $C_{70}$-금 나노입자 필름을 노출하여 초음파를 조사 시킨후 고체 표면 위에 부분적인 탈착도의 변화와 작은 정도의 응집성이 일어남을 알 수 있었다.

Heat-induced coarsening of layer-by-layer assembled mixed Au and Pd nanoparticles

  • Shon, Young-Seok;Shon, Dayeon Judy;Truong, Van;Gavia, Diego J.;Torrico, Raul;Abate, Yohannes
    • Advances in nano research
    • /
    • 제2권1호
    • /
    • pp.57-67
    • /
    • 2014
  • This article shows the coarsening behavior of nanoparticle multilayers during heat treatments which produce larger metallic nanostructures with varying shapes and sizes on glass slides. Nanoparticle multilayer films are initially constructed via the layer-by-layer self-assembly of small and monodispersed gold and/or palladium nanoparticles with different compositions (gold only, palladium only, or both gold and palladium) and assembly orders (compounding layers of gold layers over palladium layers or vice versa). Upon heating the slides at $600^{\circ}C$, the surface nanoparticles undergo coalescence becoming larger nanostructured metallic films. UV-Vis results show a clear reliance of the layering sequence on the optical properties of these metal films, which demonstrates an importance of the outmost (top) layers in each nanoparticle multilayer films. Topographic surface features show that the heat treatments of nanoparticle multilayer films result in the nucleation of nanoparticles and the formation of metallic cluster structures. The results confirm that different composition and layering sequence of nanoparticle multilayer films clearly affect the coalescence behavior of nanoparticles during heat treatments.