Synthesis And Characterization Of Micro/Nano Spherical Materials Based On Glucose

Controllable synthesis of materials is of significant importance for their technological application and fundamental research. The synthetic procedure is the key issue for obtaining materials with controllable size, morphology, dimension, monodispersity and unique properties. Spherical materials, especially those with hollow structures, possess tailorable structures, low densities, high surface areas, and unique optical, electrical, and surface properties. They might meet the needs of scientists and have promising applications in vast areas of miniature sensors, artificial cells, fillers, catalysts, acoustic insulation, microchip reactors, delivery vehicle systems, and photonic crystals.This thesis focuses on the preparation of several functional materials, including carbon spheres, metal oxide spheres with hollow structures and metal oxide encapsulated Ag nanoparticles, with glucose as the starting materials. The as-obtained products were characterized by SEM, TEM, XRD, FTIR and TG techniques.The main results are summarized as follows:(1) Diverse morphologies of carbon materials were fabricated under hydrothermal condition with glucose as the carbon precursor. In the absence of surfactant, carbon spheres with different diameters have been controllably prepared by tuning the experimental factors, such as reactant concentration, reaction time and temperature. Carbon materials with elliptic, pear-like, and bowl-like morphologies were prepared with the assistance of a non-ion surfactant Tween 80. The surfaces of the carbonaceous materials were occupied by abundant oxygen-containing functional groups.(2) ZnO spheres with hollow structures have been prepared with the glucose-based carbonaceous materials as template. During the synthetic process, zinc/carbon hybrid microspheres are firstly acquired and then the carbon was eliminated by oxidation in air at elevated temperature. It was found that concentration of oxygen significantly has an influence on the ZnO hollow structures obtained. ZnO hollow spheres were formed when the oxidation occurred at low oxygen concentration, however, urchin-like materials made of ZnO nanorods were obtained at high oxygen concentration.(4) Coupling the reduction of noble metal salts and carbonization of glucose, Ag@C core/shell structures are synthesized. Using these Ag@C core-shell structures as template, several metal oxides hollow spheres encapsulated Ag nanoparticles are successfully synthesized.