Preparation And Characterization Of Silica Composite Materials And Fluorescent Conjugated Polymers

Nanomaterials have attracted widely interest due to unique physical andchemical properties. The morphology of nanomaterials plays an important role tomaterials properties. Thus the development of the novel preparation approach tomaterials has become an important field. Most of the present preparation approachinvolved in complex preparation process, high temperature and high pressure and soon. In the present research, we have developed series of simple preparation approachto inorganic and organic optical materials. The whole work can be divided into threeparts. More details are shown as following:1. In the first research work, silver nanoparticles doped silica compositematerials are prepared by the combination of in situ reduction and sol-gel techniques.First, we prepared silicon dioxide nanotubes with silver nanoparticle in inner wall bytwo steps sol-gel approach at room temperature. The possible formation mechanismwas suggested. The influence of the preparation condition on the materialsmorphology was investigated. The obtained materials were characterized by SEM andFETEM. The properties and composition of the synthesized materials were alsoinvestigated by Uv-Vis and FTIR, respectively. Secondly, silver nanoparticles dopedsilica hybrid materials were fabricated by “one-pot” sol-gel technique in nonaqueoussolutions at room temperature. The columniform shaped micro-rods, nanobelt andhexagon shaped micro-rods were obtained by controlling the preparation conditions.The main factors that affect the morphology of hybrid materials were investigated indetail. The materials were further characterized by SEM and FETEM and theproperties were checked by Uv-Vis. The results indicated that different morphologysilver nanoparticles doped hybrid materials could be obtained by adjusting thereaction conditions.2. In the second research work, CdS and pbS quantum dots doped silica hybridmaterials were obtained by sol-gel technique at room temperature. The morphologychange was studied by adjusting the preparation conditions. The morphologies of synthesized materials were further characterized by SEM and TEM, respectively. Thefluorescence properties were also checked by fluorescence spectrometry. The resultsindicated that the obtained materials showed excellent fluorescence properties.3. Chrysanthemum, square tube and dendritic conjugated polymers wereprepared by a simple one-pot approach in the absence of any template. The effect ofmain factors such as initiator type and amount, the concentration of functionalmonomer, methyl orange and protein on morphology was investigated in detail.. Themorphology of the materials was checked by SEM and TEM, respectively.Fluorescence properties of prepared materials were also investigated in differentorganic solvents by fluorescence spectrometry. All results indicated the synthesizedmaterials show a potential in fluorescence sensor.