| Summary: | 碩士 === 國立成功大學 === 化學系專班 === 94 === In this thesis, mesostructured “phenolic formaldehyde resin -poly ethylene glycol-silica” (PF-PEG-SiO2) nanohybrid was synthesized by using PF-PEG polymer blend as organic template and sodium silicate as silica source. At pH » 5.0, the silica species and PEG-PF polymer blend can mutually assembly through the hydrogen-bonding interaction. After carbonization at high temperature under Nitrogen atmosphere, a “silica-carbon” nanocomposite was obtained.
The Silica-Carbon composite can be used directly in the application of solar absorbance. The silica-carbon nanocomposite prepared with a proper amount of sodium silicate solution and carbonization temperature shows better heat absorbing efficiency and similar heat releasing rate related to bamboo carbon. Because of the simple synthetic process, the silica-carbon nanocomposite can be easily synthesized in a large scale that can replace the bamboo carbon to be used as a new solar absorbance material.
After removed silica part of the silica-carbon nanocomposite, a mesoporous carbon with high surface area and large pore volume was obtained. When a proper amount of metal oxides were loaded onto the surface of the mesoporous carbon, and then treated at 500 - 900 ℃ under inert gas environment, a hydrophilic “metal@carbon” material with magnetism can be synthesized via a reduction procedure of the metal oxides by the carbon. When the metal oxide loaded onto the mesoporous carbon was treated at above 700 ℃ in acetylene / argon, the metal oxide can catalyze the growth of the carbon nanofibers or nanotubes on the surfaces of the mesoporous carbon spheres. Thus, a good electric conducting “carbon nanotube-mesoporous carbon” composite can be readily prepared.
In the last part, “PF-F127-calcium phosphate” hybrid was also synthesized by using F127 and PF blend as organic template. With a well control on the blending time, the components of CaCl2 and H3PO4 and pH value, a film-like mesoporous carbon with surface area above 1000 m2/g and pore volume above 2.0 cm3/g was obtained from carbonization and inorganic template removal by using hydrochloric acid. This synthetic method can avoid the disadvantage of using highly dangerous hydrofluoric acid in the silica-removal processes.
|
|---|
