Chen, Jixin (2010-05). Nanofabrication, Plasmon Enhanced Fluorescence and Photo-oxidation Kinetics of CdSe Nanoparticles. Doctoral Dissertation. Thesis uri icon

abstract

  • Unconventional nanofabrication techniques; both those which have been newly developed and those under development, had brought inexpensive, facile, yet high quality means to fabricate nanostructures that have feature sizes of less than 100 nm in industry and academia. This dissertation focuses on developing unconventional fabrication techniques, building studying platforms, and studying the mechanisms behind them. The studies are divided into two main facets and four chapters. The first facet, in Chapter II and Chapter III, deals with the research and development of different nanofabrication techniques and nanostructures. These techniques include litho-synthesis, colloidal lithography, and photolithography. The nanostructures that were fabricated by these techniques include the metal nanoparticle arrays, and the self-assembled CdSe nanoring arrays. At the same time, the dissertation provides mechanisms and models to describe the physical and chemical nature of these techniques. The second area of this study, in Chapter III to Chapter V, presents the applications of these nanostructures in fundamental studies, i.e. the mechanisms of plasmon enhanced fluorescence and photo-oxidation kinetics of CdSe quantum dots, and applications such as molecular sensing and material fabrication. More specifically, these applications include tuning the optical properties of CdSe quantum dots, biomodification of CdSe quantum dots, and copper ion detection using plasmon and photo enhanced CdSe quantum dots. We have successfully accomplished our research goals in this dissertation. Firstly, we were able to tune the emission wavelength of quantum dots, blue-shifted for up to 45 nm, and their surface functionalization with photo-oxidation. A kinetic model to calculate the photo-oxidation rates was established. Secondly, we established a simple mathematical model to explain the mechanism of plasmon enhanced fluoresce of quantum dots. Our calculation and experimental data support the fluorescence resonance energy transfer (FRET) mechanism between quantum dots and the metal nanoparticles. Thirdly, we successfully pattered the CdSe quantum dots (diameter ~4 nm) into nanorings with tunable diameters and annular sizes on different substrates. We also established a physical model to quantitatively explain the mechanism with the forces that involved in the formation of the nanorings.
  • Unconventional nanofabrication techniques; both those which have been newly
    developed and those under development, had brought inexpensive, facile, yet high
    quality means to fabricate nanostructures that have feature sizes of less than 100 nm in
    industry and academia. This dissertation focuses on developing unconventional
    fabrication techniques, building studying platforms, and studying the mechanisms
    behind them.
    The studies are divided into two main facets and four chapters. The first facet, in
    Chapter II and Chapter III, deals with the research and development of different
    nanofabrication techniques and nanostructures. These techniques include litho-synthesis,
    colloidal lithography, and photolithography. The nanostructures that were fabricated by
    these techniques include the metal nanoparticle arrays, and the self-assembled CdSe
    nanoring arrays. At the same time, the dissertation provides mechanisms and models to
    describe the physical and chemical nature of these techniques.
    The second area of this study, in Chapter III to Chapter V, presents the
    applications of these nanostructures in fundamental studies, i.e. the mechanisms of
    plasmon enhanced fluorescence and photo-oxidation kinetics of CdSe quantum dots, and
    applications such as molecular sensing and material fabrication. More specifically, these
    applications include tuning the optical properties of CdSe quantum dots, biomodification
    of CdSe quantum dots, and copper ion detection using plasmon and photo
    enhanced CdSe quantum dots.
    We have successfully accomplished our research goals in this dissertation.
    Firstly, we were able to tune the emission wavelength of quantum dots, blue-shifted for
    up to 45 nm, and their surface functionalization with photo-oxidation. A kinetic model
    to calculate the photo-oxidation rates was established. Secondly, we established a
    simple mathematical model to explain the mechanism of plasmon enhanced fluoresce of
    quantum dots. Our calculation and experimental data support the fluorescence
    resonance energy transfer (FRET) mechanism between quantum dots and the metal
    nanoparticles. Thirdly, we successfully pattered the CdSe quantum dots (diameter ~4
    nm) into nanorings with tunable diameters and annular sizes on different substrates. We
    also established a physical model to quantitatively explain the mechanism with the
    forces that involved in the formation of the nanorings.

publication date

  • May 2010