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常压碱熔-水热法制备了银掺杂TiO2复合纳米管。氮吸附法测定其比表面积与原料相比,增加了2.3倍,达82m2/g。用XRD、TEM和XPS进行了表征。TiO2纳米管由锐钛矿相和金红石相组成,研究表明复合纳米管中银元素以金属银和氧化银状态共存。因长径比增大,其XRD衍射峰峰高和峰强均大幅度降低。UV-Vis吸收光谱显示,银掺杂TiO2复合纳米管的吸收光谱发生了红移,带边红移近40nm。这是因为在TiO2纳米管表面形成了肖特基结,TiO2禁带宽度之间形成了杂质能级,使其表观禁带宽度减小,有助于光生电子的迁移,减少电子-空穴复合;纳米管表面羟基氧(—OH)使其表面的酸性活性点增加,增强了价带中光生空穴的氧化能力。
Silver-doped TiO2 composite nanotubes were prepared by atmospheric pressure alkali-hydrothermal method. Nitrogen adsorption method to determine the specific surface area compared with the raw material, an increase of 2.3 times, reaching 82m2 / g. Characterization by XRD, TEM and XPS. TiO2 nanotubes by the anatase phase and rutile phase composition, studies have shown that composite silver nanotubes in the silver and silver oxide state coexistence. Due to the increase of the aspect ratio, the peak height and the peak intensity of XRD diffraction significantly decrease. The UV-Vis absorption spectra show that the absorption spectra of silver-doped TiO2 composite nanotubes have been red-shifted with a red shift of nearly 40 nm. This is because the formation of Schottky junction in the surface of TiO2 nanotube, TiO2 band gap between the formation of an impurity level, the apparent band gap decreases, contributing to the migration of photo-generated electrons, reducing electron-hole Compound; the hydroxyl oxygen (-OH) on the surface of the nanotube increases the active sites on the surface of the nanotubes, which enhances the oxidation ability of photogenerated holes in the valence band.