Self-assembly Of Colloidal Particles At The Air/liqiud And Liquid/liquid Interface

Self-assembly pattern structures of monodisperse colloidal particles with different nanoscopic materials have found wide potential applications in optical, magnetic, and electronic properties. Recently, its paperation has attracted many researchers'interest and attention. In this dissertation, the preparation of pattern structure using different colloidal particles has been realized by two ways: i.e. self-assembed colloidal particles at the air-liquid interface and liquid-liquid interface. Besides, the structure and the optical properties of the pattern structure thin film which was fabricated at the interface were studied. And the self-assembly mechanism at the liquid-liquid interface was also discussed primarily. The main results obtained in this dissertation are listed as below:1. We synthesized different diameters of silicon dioxide particles by changing the content of tetraethyl orthosilicate using Stober method. Photonic crystals consisted of regular arrange of uniform diameter of particles were fabricated at the air-liquid interface through the evaporation of colloidal suspension. The UV-visible transmission spectra of SiO₂ three-dimensional pattern arrays was characterized. And, we deduce theory dirrraction peak position of corresponding particles by bragg diffraction theory and compare with the experiment results.2. The surfaces of silicon dioxide particles were modified with 3-methacryloxypropyl- trimethoxysilane through reflux. Self-assembly of these modified particles at the liquid-liquid interface. Then, the thin film was stabilized through photo-initiation polymerization which strengthens the film and preventes it from changing the structure when it was taken out from the interface. We found the proper condition for the fabrication of ordered thin film by optimizing the experiment factors including the concentration of modified particles and the assembly time.3. We synthesized uniform Fe₃O₄ nanoparticles using hydrothermal method. The impact factors: i.e. concentrations of reactants, reactive time have been studied in our experiment. We got the optimized condition. And we found the optimized condition. We also assembled these uniform particles at the air-liquid and liquid-liquid interface at different magnetic field and discussed the results paimarily.4. We synthesized Fe₃O₄@SiO₂ nanoparticles and Fe₃O₄-KH570 nanoparticles using sol-gel method and reflux method respectively. And we assembled these modified particles at liquid-liquid interface. The impact factors such as the concentration of modified Fe₃O₄ nanoparticles and the magnetic field also have been studied in our experiment.