Template Method Preparation, Characterization And The Photocatalytic Performance Of Low-dimension Ordered Titania Arrays

The effect of anodic voltage, anodizing time, the temperature of the electrolyte, the electropolishing technology, the heat treatment of aluminium foil and the cathode materials were studied systemically in the two-step anodizing process. In addition, the effect of anodic voltage, anodizing time, the temperature of the electrolyte and pore-extending time on the pore size were also discussed. Through the study of the anodizing process in the oxalic acid/ethanol electrolyte, it was found that the formation process of the porous membrane was not changed by the additive of ethanol. The main effect of ethanol is to reduce the chemical and electrochemical solution rate and it is possible to adjust the pore diameter by controlling the anodic voltage at room temperature. The formation process of porous alumina was observed using Field Emission SEM in the oxalic acid/ethanol electrolyte and at lower reaction temperature. The process consists of not only the formation of barrier layer, appearance of tiny pores and the stable growth of pores but also the mid-process of different pores incorporating each other by competition and cooperation mechanism. It provides a new experimental support for the study and preparation of porous templates. A two-step anodizing process was used to prepare porous alumina templates with adjustable diameter in the range of 10～200nm in the oxalic acid/ethanol electrolyte. A new self-organized growth mechanism was established for the formation process of porous alumina according to the theory on dissipative structure.The preparation process of titania nanoarrays in sol-gel template method was studied. It was found that the sol could enter the pores more easily in a certain negative pressure condition. This method solved the difficulty in preparation of nanoarrays using sol with high concentration and templates with small pore diameter by sol-gel template method. The titania nanowire and nanotube arrays with high quality and small diameter were successfully prepared in this method. The membrane with periodical modulating titania nanodot arrays was first prepared using the alumina concave-hole membrane template in sol-gel method. The morphology and structure of the membrane surface were modulated artificially. The surface modulating structure was iso-epitaxy titania nonodot- arrays.Sol-electrophoresis method was used to prepare titania nanowires with two shapes in the pores of porous alumina template. In addition, the nanowires with shape...