Sonochemical Synthesis Of Morphogenetic Materials And Investigation Of Its Optic Properties

Scientists are always amazed by the biological materials, which are characterized by unique structures and morphologies. These materials possessed the integrated functions with the hierarchical microstructures coupled with their components. Butterfly wings show unique visual exhibitions because of the most complicated hierarchical microstructures on their wings, which is of inspiration for researchers. Chloroplasts, which serve as favorable places for the light-harvesting and energy conversion within an intricate cylindrical lamellar system, enlighten us to reproduce morphogenetic materials for light absorbance.Inspired by these special and complex hierarchical microstructures, we focused on studying the transformation and characterization of titanium dioxide from biomaterials, such as butterfly wings and chloroplast. It can be divided into four parts as follows:1. A new sonochemical method was developed for the fabrication of morphogenetic materials from butterfly wings, based on the careful study of the components and thermo-properties of the original butterfly wings. The precise replication of butterfly wings could be obtained in TiO₂ through calcination.2. The key factors of sonochemical reaction time, the precursor concentration were optimized. The dependence of morphogenetic TiO₂ with butterfly wings structure on calcination temperatures has been investigated. Accordingly, the optical properties of the resultant TiO₂ materials were studied by using microspectrameters, which showed that the wings with different sizes of microstructures have different reflectance colors. The optimal calcinations temperature was thus obtained for fabricating morphogenetic TiO₂ materials from butterfly wings.3. Replication of butterfly wing with photonic structures and Quasi-honeycomb like structure in TiO₂ and assembling of ordered mesopores inside by using a sonochemical method. The resultant material presented high surface area owing to the hierarchical structure and the well-distributed mesopores. The combination of functionality of the inorganic oxide, the fine hierarchical biological structures and high surface area contributed to the improved light absorbance ability. It is expected that the TiO₂ has a great potential use in photocatalysis, water splitting and DSSC.4. Fabrication of biomorphic TiO₂ using granum as template by means of ultrasonication and calcination. The layered nanostructure of granum was replicated successfully in TiO₂ with higher surface area and better light-harvesting property. The nano-layered TiO₂ was applied as a novel photoanode material in DSSC and exhibited the highest short-circuit density, energy conversion efficiency, in comparison with the TiO₂ replica using conventional impregnation method and commercial P25.