Fabrication Of Polymerized Crystalline Colloidal Arrays And Their Sensing Applications

The focus of this thesis is the development of novel materials that called a crystalline colloidal array (CCA). At low ionic strengths, repulsion between monodisperse, highly charged colloidal particles forces the colloidal spheres into a minimum energy configuration, which is either a body- or face-centered cubic lattice. CCA diffracts visible light, and the diffraction obeys Bragg's law.We have fabricated a CCA by sedimentation and resuspension to wipe off the excess ion of the suspensions, and locked the order of the CCA embedding the CCA into a poly network (PCCA). The PCCA copies the optical properties of the CCA whose reflected wavelength almost can cover all the visible region.Studied on the environmental effect on the PCCA based upon immersing the PCCA in the ethanol solutions, and the PCCA shifts the Bragg reflective peak proportional to the concentration of the ethanol. The fact reveals the PCCA is very sensitive to the varying of the circumstance that 1% change of ethanol proportion in the range of 0-25% causes the PCCA to shift the photonic crystal diffraction 10 nm.This thesis describes a novel method for functionalizing PCCA. We have successfully hydrolyzed the PCCA and incorporated 3-Aminophenylboronic acid into the PCCA and fabricated the intelligent polymerized crystalline colloidal arrays (IPCCA). The hydrolyzed PCCA can detect pH in the 2.2-9.6 range, and its resolution ratio is 1.2nm/0.01pH. At low metal concentrations, the glucose covalently attaches to the intelligent polymerized crystalline colloidal array, which causes it to swell. The diffraction peak of the PCCA can shift in the range of 65 nm, and the sensitivity and the response range of the PCCA are superior to the close-packed photonic crystal, which are potentially valuable in a number of sensing applications.The PCCA is a mesoscopically periodic crystalline colloidal array of spherical silica colloids polymerized within a thin, intelligent polymer hydrogel film and can efficiently diffract visible light meeting the Bragg condition. Throughout the experimentation we use little expensive apparatus and realize the sensor materials, which are sensitive to the condition varying in a wide range, specificity, low cost, operated simply and commercial.