摘要
首次以不同咪唑基离子液为结构导向剂，通过水热合成制备出介孔TiO2分子筛。考察了合成条件对产物结构的影响，结果表明，离子液用量、离子液类型、晶化温度、晶化时间等因素对TiO2介孔分子筛的形成和孔道结构均有影响，其中晶化温度及离子液类型的影响最为明显，在较低晶化温度时（100℃）产物孔径分布范围宽，但仍为介孔结构，当温度升高到180℃时，孔径变大并开始失去介孔特征，机理为晶化温度会影响离子液与无机物的相互作用速度，高温时TiO2结晶度也会迅速提高导致失去介孔结构，最佳晶化温度为120℃；咪唑基离子液其碳链长度不同，使用短链离子液时产物无介孔结构，当使用长链离子液时产物孔道结构良好，作为结构导向剂其碳链长度会决定产物孔道生长趋势和长度，最佳离子液类型为[C16MIM]Br．X射线衍射谱（XRD）表明产物为锐钛矿型介孔TiO2；透射电镜（TEM）观察表明产物具有规整的孔道结构（3～4nm），与低温氮吸附法分析结果一致；激光粒度分析表明产物粒度较小（20～40nm）并且分布范围窄。
TiO2 mesoporous molecular sieves were synthesized by the hydrothermal method using different ionic liquids as template at first time. The effects of synthesis conditions on the structure of TiO2 were investigated, including the molar ratio of Ti source and ionic liquids, the type of ionic liquids, crystallization temperature and time, especially the crystallization temperature and type of ionic liquids. TiO2 mesoporous molecular sieves were of wide pore diameter but still was mesoporous structure at 100℃ while it lose its mesoporous structure at 180℃. The mechanism was that the speed of interaction between ionic liquids and inorganic compound was affected by crystallization temperature. When crystallization temperature was enhanced to high enough, TiO2 lose its mesoporous structure because of the degree of crystal increasing. The different chain in ionic liquids can influence the results too. When ionic liquids of short chain were used as template, the samples didn＇t have mesoporous structure. When ionic liquids of long chain were used as template, the samples have good mesoporous structure. Pore growth tendency and length would be decided by the different of ionic liquids would decide. The best ionic liquid were [C16MIM]Br. X-ray diffraction results showed that the samples were anatase TiO2 mesoporous. The TEM images demonstrated that the samples had the orderly pore structure and pore diameter between 3nm to 4nm, and the results can match the N2 adsorption well. The Laser Particle Size analyzed indicated that the size of the samples was small （20-40nm） and the scope of size was narrow.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2007年第A07期2476-2480,共5页
Journal of Functional Materials
基金
安徽省教育厅科研基金资助项目（2006kj288）
国家自然科学基金资助项目（20673042）
关键词
离子液
介孔TIO2
水热合成
ionic lignids
mesoporous TiO2
hydrothermal method
