超声波作用下的钛醇盐水解法制备纳米TiO_2  

Sonochemical Synthesis of Nanocrystalline TiO_2 by Hydrolysis of Titanium Alkoxides

作　　者：国伟林[1,2] 王西奎[3] 林志明[1] 宋广智[1] 

机构地区：[1]中国科学院理化技术研究所微珠材料工程研究中心 [2]济南大学化学与环境工程学院,济南250022 [3]济南大学化学与环境工程学院

出　　处：《高等学校化学学报》2002年第8期1592-1594,共3页Chemical Journal of Chinese Universities

基　　金：山东省自然科学基金 (批准号 :Z2 0 0 0 B0 1)重点资助

摘　　要：Nanocrystalline TiO 2 has been studied extensively in recent years as photocatalysts to deal with environmental pollutions, such as water purification, wastewater treatment and air purification. Here a novel sonochemical method for directly preparing anatase nanocrystalline TiO 2 has been established. Nanocrystalline TiO 2 were synthesized by the hydrolysis of titanium tetrabutyl in the presence of water and ethanol under a high intensity ultrasonic irradiation(20 kHz, 100 W/cm 2) at 363 K for 3 h. The structure and particle sizes of the product were dependent upon the reaction temperature, the acidity of the medium and the reaction time. Characterization was accomplished by using various different techniques, such as powder X ray diffraction(XRD), transmission electron microscopy(TEM), thermogravimetry differential thermal analysis(TG DTA) and Fourier transform infrared(FTIR) spectroscopy. The TEM images showed that the particles of TiO 2 were columnar in shape and the average sizes were ca. 3 nm×7 nm . The formation mechanism of nanocrystalline TiO 2 under a high intensity ultrasonic irradiation was also investigated. The hydrolytic species of titanium tetrabutyl in water condensed to form a large number of tiny gel nuclei which aggregated to form larger clusters. Ultrasound irradiation generated a lot of local hot spots within the gel and the crystal structural unit was formed near the hot spots with the decrease of the gel nuclei, which lead to form nanocrystal particles.Nanocrystalline TiO 2 has been studied extensively in recent years as photocatalysts to deal with environmental pollutions, such as water purification, wastewater treatment and air purification. Here a novel sonochemical method for directly preparing anatase nanocrystalline TiO 2 has been established. Nanocrystalline TiO 2 were synthesized by the hydrolysis of titanium tetrabutyl in the presence of water and ethanol under a high intensity ultrasonic irradiation(20 kHz, 100 W/cm 2) at 363 K for 3 h. The structure and particle sizes of the product were dependent upon the reaction temperature, the acidity of the medium and the reaction time. Characterization was accomplished by using various different techniques, such as powder X ray diffraction(XRD), transmission electron microscopy(TEM), thermogravimetry differential thermal analysis(TG DTA) and Fourier transform infrared(FTIR) spectroscopy. The TEM images showed that the particles of TiO 2 were columnar in shape and the average sizes were ca. 3 nm×7 nm . The formation mechanism of nanocrystalline TiO 2 under a high intensity ultrasonic irradiation was also investigated. The hydrolytic species of titanium tetrabutyl in water condensed to form a large number of tiny gel nuclei which aggregated to form larger clusters. Ultrasound irradiation generated a lot of local hot spots within the gel and the crystal structural unit was formed near the hot spots with the decrease of the gel nuclei, which lead to form nanocrystal particles.

关 键 词：超声波 钛醇盐 水解法 制备 纳米TiO2 二氧化钛 超声化学 制备 锐钛矿 

分 类 号：TB383[一般工业技术—材料科学与工程]