Exploration Research On Synthesis And Coupling Properties Of Functional Oxides With Butterfly Wings Hierarchical Structure

Scientists are always amazed by the biological materials evolved millions of years, which are characterized by unique structures and morphologies. These materials possessed the integrated functions with the hierarchical microstructures coupled with the components. Occurred on the earth in Tertiary period 25 MYA (around million years ago), the butterfly family possesses the largest number of species (about 100 000 species), which also have the most complicated hierarchical microstructures on their wings. A butterfly's wing is a uniquely visual exhibition, not only of the aesthetics of nature, but of the machinery of evolution and of inspiration of research. They are made of scales which are quite small and form two or more layers over the wing membrane.Allured by butterfly wings special and complex hierarchical microstructures, this paper dedicated to studying on the transformation and characteristics of the inorganic butterfly wings. Based on the morph-genetic materials fabrication theory, a series of functional oxides with butterfly wings'microstructure are obtained in this study. This study was divided into five parts as follows:1. Design a special fabrication method of morph-genetic oxides with butterfly wings microstructure, based on the careful study of the components and thermo-properties of the original butterfly wings. The influences of synthesis'parameters on the morphology and elements of the morph-genetic oxides are carefully analyzed, such as the pretreatment methods, proper concentration of precursors, environment parameters (Temperature and Time etc.) of soaking method and so on. The key factor of fabrication method is the calcination roadmap, for the original butterfly wings templates and the precursors have different thermal decomposition manner. By adjusting all of the parameters mentioned above, integrate and precise butterfly wings microstructure could be maintained in the morph-genetic oxides.2. Using microspectrameters, the optical properties of the original butterfly wings and morph-genetic ZnO materials are studied on the micro areas on the samples. The results show that the wings with different microstructures have different colours. Also the inner, outer and the overlap area of the scales have variety colours, which are due to the interaction of the hierarchical structures and the lights.3. Based on the measurements and statistics of the microstructures from different scales, a two-dimension crossingrib structure module was build up. Using Gsolver5.1, all the optical properties of the scales involved in the paper were calculated and simulated. The influences of the microstructure size parameters and the refraction index on the optical properties are carefully studied. Coupling relations between the hierarchical microstructure and the lights could be used for the design of optical functional devices with butterfly wings structure in the future.4. The cathodoluminescence properties of the morph-genetic ZnO are analyzed. Using random emitted theory, the unusual cathodoluminescence behaviors of the morph-genetic ZnO are explained based on the measurements and statistics of the microstructure parameters. Not only the emitting intensities can be influenced, but also the emitting peaks positions are changed due to the coupling effect between the microstructures and emitting lights.5. A novel photoanode structure inspired by butterfly wing scales is fabricated with potential application on solar cell. Quasi-honeycomb like structure, shallow concavities structure and cross-ribbing structure were synthesized to a fluorine-doped tin oxide-coated glass substrate using butterfly wings as biotemplates. The morphology of the photoanodes, which were maintained from the original butterfly wings, was characterized by scanning and transmission electron microscopes. The calcined butterfly wings structures photoanodes were fully crystalline with arranged ridges and ribs consisting of nanoparticles. Analysis of visible light absorption spectra measurements indicates that the light-harvesting efficiencies of the quasi-honeycomb like structure photoanode were higher than the normal titania photoanode without biotemplates owing to the special microstructures.According the researches mentioned above, the butterfly wings hierarchical microstructures are maintained integrately and precisely in the morph-genetic oxides. Some novel properties of the morph-genetic oxides are studies for potential applications in optical devices, such as DSSC. Also, the fabrication method may be applied to other metal oxide systems that could eventually lead to the production of optical, magnetic or electric devices or components as building blocks for nanoelectronic, magnetic or photonic integrated systems.