不同模板剂制备介孔纳米γ-氧化铝及表征

Preparation and characterization of nano-sized mesoporous γ-Al_2O_3 with different templates

分别以十二烷基苯磺酸钠（DBS）、溴化十六烷基三甲铵（CTAB）和吐温-80（TW-80）为模板剂,以硝酸铝为铝源,采用溶胶-凝胶法制备介孔纳米γ-氧化铝。用X射线衍射（XRD）、氮气吸附-脱附、透射电镜（TEM）对样品进行表征;考察了模板剂的种类及用量对产品性能的影响。实验结果表明：采用3种不同模板剂合成的前驱体经550℃煅烧所得产物均为具有孔道结构的介孔纳米γ-氧化铝,其中采用CTAB为模板剂合成的样品其比表面积为551.8 m2/g,平均孔径为6.68 nm,孔径分布较窄（2~16 nm）,孔容为0.922 cm3/g,比采用另外两种模板剂合成的样品其孔道分布更均匀,排列更规则致密,孔径分布明显变窄,比表面积有一定程度的增大。

Different nano-sized mesoporous y - Al2O3 were synthesized by sol - gel process using Al （ NO3 ） 3 . 9H2O as aluminum source, with sodium dodecyl-benzenesulfonate （ DBS ） , eetyltrimethyl ammonium bromide （ CTAB ） , and Tween - 80 （ TW - 80 ） as templates respectively. Samples were characterized by XRD, N2 absorption - desorption, and TEM, and the influences of type and amount of template on product＇s performances were also investigated. Results indicated that precursors synthesized by three different template agents, all turned to nano-sized mesoporous y - Al2O3 with porous structure after calcination at 550 ℃. Specific surface area, average pore diameter, pore size distribution, and pore volume of the sample synthesized by CTAB were 551.8 m2/g,6.68 nm,2 - 16 nm , and 0. 922 cm3/g, respectively. Compared with those synthesized by DBS or TW - 80, CTAB resulted in more homogeneous pore distribution, more compact and regular pore arrangement, obviously narrower pore size distribution,and a certain extent increase of specific surface area.