带状氧化钛纳米晶的制备

Synthesis of titanium dioxide nanobelts

以工业制备氧化钛的中间产物（Ti（OH）4）为原料，在180～230℃的碱性条件（KOH溶液）下，采用压力热晶法成功制备出了带状TiO2纳米晶．X射线衍射（XRD）结果表明，制得的TiO2为锐钛矿结构．扫描电镜（SEM）和透射电镜（TEM）观察显示，TiO2纳米晶平均带宽为10～15nm，长度为几十到几百微米左右．研究表明，原料的预处理和反应温度直接影响纳米晶的生长．前驱物pH值为14，陈化时间为12h，生成的纳米晶较长，形貌一致；随着温度的升高，产物的晶化程度增加．最后，对带状TiO2的形成机制也进行了讨论．

TiO2 nanobelts were successfully prepared by pressure-thermalcrystallization method in alkaline solution（KOH） at the temperature ranging from 180℃ to 230℃ using the medial product Ti（OH）4 as raw material, which obtained from the industrial synthesized process of TiO2. X ray diffraction（XRD） results showed that TiO2 was anatase structure; Scanning electron microscopy（SEM） and transmission electron microscopy（TEM） observations demonstrated the average width of TiO2 was 10～15 nm, with the lengths in the range of several tens to several hundreds micrometers. Further studies implied that the pretreatment of raw material and temperature influence the growth of nanocrystal directly. Longer TiO2 with uniform size and good quality were obtained when the pH value of solution was 14 and the aged time was 12 hours; the crystallization degree increased with increasing temperature. The formation mechanism of TiO2 nanobelts was interpreted at last.