Development of Self-assembly Templating Methods for Architecture of Porous Core-shell Nanocomposites

Abstract

In recent years, there have been tremendous efforts in the synthesis of nanomaterials for their unique properties and applications different from their bulk counterparts. To incorporate multiple functionalities into one individual nanostructure is a challenging and interesting field in nanomaterial synthesis. Though various chemical routes have been developed to prepare core-shell nanocomposites, it is still believed that explorations of novel synthetic methodology and further engineering on shell structures will contribute new properties and applications to this field. This work focuses on the study of core-shell nanocomposites, aiming for producing complex nanostructures with process facility and feature application performance. Self-assembly templating is the main approach throughout this thesis, though hard-templating method is involved in some part the study. Four kinds of nanocomposites are obtained: TiO2-Polyaniline (PAN) core-shell nanomaterials, hierarchically designed SiO2-TiO2-PAN nanostructures, mesoporous SiO2 spheres with hexagonally packed vertical channels and encapsulation of nanoparticles (Au, PAN, etc.), and mesoporous Au-SiO2 core-shell nanocomposite. Material information of phase, composition, valence, and morphology are acquired from instrumental analysis such as XRD, XPS, TEM and BET etc, which help us to further understand formation mechanisms. In order to evaluate the applicability, some of these nanocomposites are used as photocatalysts or nanoreactors.