Research On The Interaction Mechanism Between Metal Nano Plasma And Bi₂S₃ Quantum Dots

The use of localized surface plasmon characteristics of metal nanoparticles enhanced optical properties of quantum dots is a hot topic in nanoscience and nanotechnology. In order to study interaction mechanism of metal nanoparticles and quantum dots, this paper mainly study the fluorescence enhancement effect of Ag nanoparticles and quantum dots hybrid materials and different morphologies of Ag colloid film and fluorescence quantum dots composites, and explore the electromagnetic enhancement mechanism caused by surface plasmon resonance.In this paper, the history, characteristics, application of surface plasmon coupled quantum dots is given. This paper study the optical properties of the noble metal (silver) quantum dots and hybrid materials.The main results and conclusions of this paper are as follows:1. The effects of reaction temperature and time and the ratio of reactants on the nucleation condition of quantum are studied. By changing reaction temperature and the ratio of reactant of Bi2S3 nanocrystal, different sizes of Bi2S3 quantum dots and nanorods are synthesized. The size of fluorescent quantum dots can be controlled, the growth mechanism is system analysis, and the fluorescence property of different size of the quantum dot is researched.2. The localized surface plasmon properties of metal nanoparticles have a close relationship with the size and morphology of the QDs. Firstly, the FDTD method is used to study the metal nanoparticles size and shape on the absorption spectra and extinction spectra, and then the chemical synthesis Ag nanoparticles with different morphologies, finally using sol-gel method prepared silica coated Ag nanoparticles. By varying the amount of ethyl silicate changes the thickness of Ag nanoparticles. The size of the Ag nanoparticles can be controlled, and the thickness of the package can be adjusted. The simulation and experimental data shows that extinction spectra of Ag nanoparticles red shifted with the thickness of SiO2. The resonance peak position can be adjusted by changing the size and thickness of SiO2.3. The fluorescence spectra of metal nanoparticles and quantum dots were studied. The change of metal nanoparticles concentration showed significant changes in the fluorescence intensity. By changing the distance between the metal nanoparticles and quantum dots by regulating the thickness of SiO2, the close relationship between the fluorescence intensity and the distance between the quantum dots and the metal nanoparticles was further verified. In order to study the effect of surface morphology of metal nanoparticles on the fluorescence quantum dots, silicon based Ag thin films were prepared and annealed with different temperature and time. It is found that the fluorescence intensity has a significant change.4. Design a LED based on surface plasma high modulation bandwidth. Through the embedded metal nanoparticles to the traditional LED, using metal nanoparticles localized surface plasmon characteristics, accelerate the carrier composite. LED modulation bandwidth and carrier recombination rate has a clear relationship, by speeding up the carrier compound can not only improve the led the luminous efficiency but also can improve the LED modulation bandwidth.