Preparation And Applications Of Silver/Silica Nanocomposite Particles

Today an increasing number of scientists have shown great interests in silver/silica nanocomposite particles for their unique properties and broad applications. In all metal elements, silver owns the highest heat and electricity conductivity, ideal dielectric function and higher stability. Silica has chemical stability, optical transparence and good monodispersed.In my thesis, it starts from the introduction of conventional colloidal science and the latest nanotechnology. I recommend the unique properties of single nanoparticles. Then from science developed and production needed, I point out the necessity and importance of nanocomposite particles. This thesis focuses on the preparation and significance of three different structures for nanocomposite particles: doping structure, core-shell structure and hollow structure. In the end I put forward my personal opinion on preparation of nanocomposite particles.Firstly, I use silane coupling agent to prepare silver-doped silica composite particles. Comparing to other methods, it has many advantages. I investigate the concentration of silane coupling agent and silver effecting on morphologies of the composite particles. I also try to discuss the formation mechanism of composite particles and do some characterizations.Secondly, I prepare core-shell nanocomposite particles by seed-mediated growth and chemical reduction methods basis on silver-doped silica composite particles. I discuss the different reducing agents effecting on the morphologies of core-shell particles. The optical properties are discussed especially complete core-shell structure. I also do some tests to characterize the composite particles.Finally, I use silver-doped silica composite particles to apply in two fields: photonic crystals and catalytic reduction of dye.