The Fabrication And Research Of Colloidal Crystals For Non-close-Packed Face-centered-Cubic Structure

Both the polystyrene microspheres and Silica microspheres colloidal crystals are used for preparing the design of full three-dimensional photonic bandgap crystals at visible wavelengths. In this paper,we fabricated the Polystyrene colloidal crystals by vertical deposition method ; and used etching technique with toluene and ethanol mix solution(Volume fraction is 10%) to prepare the polystyrene microspheres colloidal crystals for non-close-packed face-centered-cubic(fcc) structure. Its neighboring microspheres were connected by cylindrical tubes; we used the sol-gel technique to prepare the three-dimensional,order and macroporous TiO2 film with infiltrating the titanium sol into the polystyrene microspheres colloidal crystals for non-close-packed face-centered-cubic(fcc) structureFirstly,monodisperse polystyrene microspheres were prepared by emulsion polymerization. The standard deviation of microsphere,s diameter was less than 2%. We has analyzed the influence factors of polystyrene macroporous particle size.Secondly , we used the vertical deposition method to prepare the polystyrene microspheres colloidal crystals for close-packed face-centered-cubic(fcc) structure. Its band gap peak of transmission spectrum's approaches in 0.It explained that the polystyrene microspheres arranged orderly and the sample quality is very high.Thirdly , we used toluene and alcohol mix solution (Volume fraction is 10%)to etch the polystyrene microspheres colloidal crystals for close-packed face-centered-cubic(fcc) structure which has heated. The heating temperature was 85℃and the heating time is 2 hours. We prepared the polystyrene microspheres photonic crystals for non-close-packed face-centered-cubic(fcc) structure .And the neighbering polystyrene microspheres were connected by cylindrical tubes , L=18nm, r=106nm.,L and r were the length and the diameter of cylinder tubes . The methods that prepared the polystyrene microspheres photonic crystals for non-close-packed face-centered-cubic(fcc) structure proved a new kind of thought for the creation of colloidal photonic crystals with a full photonic band gap through templating technique.Finally, we took the polystyrene microspheres photonic crystals for non-close-packed face-centered-cubic(fcc) structure as the template and used the sol-gel technique to prepare the three-dimensional,order and macroporous TiO2 film with infiltrating the titanium sol into the template.The experimental results indicated that the infiltration time was 1min and the times of infiltration was 2 could prepare the three-dimensional,order and macroporous TiO2 thin film which has good quality.In addition ,we had the silica microspheres for the unit and used dvertical deposition to prepare the ordered and integrated silica microspheres colloidal crystals for close-packed face-centered-cubic(fcc) structure;then the silica microspheres colloidal crystals were sintered by high temperature; The silica microspheres colloidal crystals for non-close-packed face-centered-cubic(fcc) structure were prepared from etching the silica microspheres colloidal crystals for close-packed face-centered-cubic(fcc) structure by HF acid and water mix solution(the quality score of HF acid was 1.0 - wt%). The neighboring silica microspheres in the colloidal crystals were connected by cylindrical tubes,and the ratio between the diameters of neighboring silica ,s cylindrical tubes and the diameters of silica microspheres is 28.6%. Keeping the lattice constant the same with the length of cylindrical tubes, our ratio between the diameters of cylindrical tubes and the diameters of silica microspheres was better than the ratio of [7] . The results were useful for preparing the hollow spheres photonic crystal for non-closed-packed face-centered -cubic structure which has the full three-dimensional photonic bandgap.