Preparation Of Organic-Inorganic Hybrid Nanocomposite Hollow Spheres And Their Properties

In recent years, the strategy to fabricate hollow spheres and organic-inorganic hybrid nanocomposite spheres is of burgeoning interest. Hollow spheres as new advanced functional materials are becoming one focused research field, principally because of their novel properties, such as low density, high specific surface areas and infiltration ability. Organic-inorganic hybrid nanocomposite spheres possess both the processability of organic phase and the properties of inorganic phase (e.g. electrical, optical and magnetic and so on), In this study, we combined the advantages of hollow spheres and organic-inorganic nanocomposite spheres together to explore further application. Two kinds of hollow nanocomposite spheres were fabricated through the interaction between polymer chains and inorganic nanoparticles. All the research contents and results are shown as follows:(1) In the first chapter, we present a strategy for fabrication of hollow poly (N-isopropylacrylamide) (PNIPAM)-Ag nanocomposite spheres. In this approach, the thermosensitive PNIPAM hollow spheres were first synthesized via a one-pot "self-removing" process and then employed as supporters for the coordination and in-situ reduction of Ag+ ions. The results show that these hollow PNIPAM-Ag nanocomposite spheres still have typical thermal sensitivity, and more importantly, these spheres have very good and controllable catalytic activity with five stages of variation versus temperature.(2) In the second chapter, we present a "one-pot" procedure to synthesize hollow polystyrene/rare-earth-doped nanoparticles (PS/REDNPs) hybrid spheres. In this approach, when carboxyl-capped PS particles were deposited by different REDNPs in aqueous medium, such as LaF3:Eu3+, LaF3:Ce3+-Tb3+ and YVO4:Dy3+, PS/REDNPs organic-inorganic hybrid hollow spheres could be directly obtained via the in-situ diffusion of core PS chains into the voids between rare-earth-doped nanocrystals through the strong capillary force. Not only is this the first example of PS/REDNPs hybrid hollow spheres derived from capillarity force induced migration of polymer chains, but also the synthetic procedure is very simple. And the obtained hybrid hollow spheres are hydrophilic and luminescent and could be directly used in chemical and biological fields.