反应温度对水热合成二氧化钛微粒的影响

Effects of the Temperature of the System on Titanium Dioxide Particles by Hydrothermal Synthesis

采用水热合成工艺,以钛酸丁酯(Ti(OC4H9)4)为前驱体,通过改变水热合成反应的温度,合成了不同晶型和形貌的二氧化钛(TiO2)微粒。使用扫描电子显微镜和X射线衍射仪对产物进行表征。结果表明:水热反应的温度对TiO2微粒的晶型、晶粒尺寸和形貌有较大影响。随着水热反应温度的增加,二氧化钛微粒的晶粒粒径越来越大,结晶程度越来越完整,形貌也越来越规则。当水热反应温度较低时(80℃),晶型以锐钛矿为主,衍射峰峰宽较宽,峰强也较弱,晶粒刚开始发育;随着反应温度增加,开始出现金红石晶型,衍射峰锐化,峰的强度增强,晶粒粒径增大,晶粒逐渐发育完全;当反应温度达到160℃时,以金红石晶型为主,晶粒发育完全,结晶完善。

Different morphology and size of titanium dioxide particles were hydrothermally prepared by using tetrabutyl titanate（ Ti（ OC4H9 ）4 ）as precursor at different temperatures. The characteristics of TiO2 were studied by scanning electron microscopy and X-ray diffraction （XRD）. The results showed that the crystalline phase, size of the particles and morphology of TiO2 particles were greatly influenced by the temperature of the hydrothermal synthe- sis. With the increasing hydrothermal temperature, the grain size of titanium dioxide particle increased accordingly, the degree of crystallinity was more and more complete, while rules of the sample morphology was better. The producing titanium dioxide was presented with anatase phase structure priority, the XRD peaks became broaden, the peak intensity was weak and the grain started to develop, when hydrothermal temperature was low. The rutile crystal appeared with the increase of hydrothermal temperature, the diffraction peak was sharp, the peak intensity and the grain size increased. When the temperature rose to 160℃, crystal structure was mainly composed of rutile phase, with complete grain development and perfect crystallization.