| Increasing interest in nanotechnologies and biocomplexity has created the need to understand the morphogenesis of complex self-assembled shapes, which either exist in nature or can be synthesized for a specific purpose. The material obtained as a result of liquid crystal templating (hexagonal mesostructured silica, e.g., so-called MCM-41) features large variety of complex micron size shapes and sizes. This is a good test system for investigation of the morphogenesis of the nanoporous silicas. Such material is of great interest to industry since it features highly uniform nanosize porosity, and consequently, can be functionalized by putting various substances inside the pores. While the synthesis of this material is relatively well elaborated and its chemistry is understood, the mechanisms responsible for the overall morphogenesis of silica nanoporous shapes require further investigation. This is the main goal of the present work. The basic hypothesis was that the complex morphology of the shapes is a result of relaxation of mechanical stresses which appear due to differential polymerization of silica precursor. Such a difference occurs due to difference in time required to assembly different layers of the shapes, as a result of the age distinction between the older inner parts of the shapes and the younger outer layers.; The main goals of this work are to elaborate quantitatively the theory of morphogenesis of self-assembled nanoporous silica shapes, to develop experimental recipes of synthesis of specific shapes in controlled way, to predict and synthesize new shapes suitable for specific applications.; Important insights of this research open a new area of controlled synthesis of nanoporous silica shapes, contribute a new way of thinking about templated synthesis of hierarchical materials over size scales which has never been seen in solid state chemistry. The results of this work have an impact in such areas as development of new shapes as templates for nanostructures, optics and laser industry, parts for the future nano/micro-machines, biosensors, etc. The outcome of the study also provides a link to medical applications. |
