Highly dispersed mesoporous alumina fibers were successfully synthesized through urea hydrothermal-uniform precipitation method using rosin-based quaternary ammonium salt as a structure directing agent. Their structures were characterized with X-ray diffraction, N2 adsorption and desorption, field-emission scanning electron microscope and transmission electron microscope. The results indicated that well dispersed fibrous ammonium aluminium carbonate hydroxide precursors were formed under the hydrothermal treatment. After the calcinations at 823 K for 4 h, fibrous mesoporous γ-Al2 O3 were obtained. The temperatures of the hydrothermal treatments had significant influence on the textural properties of the samples. The increase of the temperatures resulted in the increase of crystallinities. However, after the calcinations, all the samples transformed intoγ-Al2 O3 phase. No distinct difference of crystal structure could be observed among the samples. When the hydrothermal temperature was 373 K, the sample possessed a larger surface area (241. 18 m2/g) with a smaller pore diameter(7. 21 nm). The increase or decrease of the hydrothermal temperatures led to the decrease of surface areas, and the increase of pore diameters. The length of the precursor fibers was about 5 μm, and the width of which was about 200 nm. After the calcinations, the morphology of the sample kept intact with porocity increased.%采用松香基季铵盐为结构导向剂,经尿素水热-均匀沉淀法成功合成出高分散纤维状介孔氧化铝。采用X射线衍射、N2-吸附脱附、场发射扫描电镜和透射电镜表征样品的结构性能。结果表明,经水热反应后,样品形成高分散的纤维状碳酸铝铵前驱体,经823 K煅烧4 h后,形成纤维状介孔γ-Al2 O3。水热反应温度的高低,对样品的微观结构有着较大的影响,水热反应温度的升高有利于前驱体结晶度的提高,但经煅烧后,样品均转变为γ-Al2 O3,且各样品晶相结构无显著差异。当水热温度为373 K时,样品比表面积相对较大(241.18 m2/g),但孔径相对较小(7.21 nm),提高或降低样品的水热反应温度会造成样品比表面积的下降,但样品的孔径会有所增大。在水热温度373 K下所得前驱体纤维长约为5μm,宽约为200 nm,经煅烧后样品形貌保存完整,且孔隙率有所增大。
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