| Nano-titania is a new functional material, and is widely used in many fields, such as photocatalysis, solar cell, gas sensor, and so on. Biomimetic synethesis technology has become a potential aspect in the field of inorganic materials preparation. The research status of nanometer titania preparation with templates in biomimetic field was a novel developing method. Comparing with the traditional sol-gel method, this template-synthesis method has advantages of controlling the crystalline structure and porous microstructure. Firstly, the synthesis conditions of titania sol was investigated. It was indicated that the H2O/Ti(OBu)4 and the AcAc/Ti(OBu)4 had important effects on the physical performance of titania sol. Secondly, influenced factors was studied on the preparation of TiO2, such as the temperature and preservation time of calcination, substrates, spinning times, the molecular weight and quantity of PEG, and so on. According to the characterizations of the titania by XRD, the crystal phase was different with the difference of the preservation time of calcination. The SEM images of the titania confirmed that the craze degree was related with the spinning times. With the increase of the molecular weights and the addition amount of PEG, the average crystal size decreased.Finally, the semiconductor properties and the sensitive mechanism of the nano-TiO2 were researched. The prepared titania thin films had good p-type behaviors to CO. The HRTEM characteristic indicated that there were some grain boundaries and defects in the titania. The XPS analysis indicated that the contents of oxygen atoms were superfluous, which resulted in the existence of vacancy metal Ti atom or interstitial atom of oxygen.
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