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用Germini表面活性剂[C12H25N+(CH3)2-(CH2)2-N+(CH3)2C12H25]·2Br-作模板合成了立方结构的介孔二氧化硅,并且用小角X射线衍射和氮气吸附-脱附技术对样品进行了表征.结果表明,所得到的介孔二氧化硅为立方结构,晶胞参数在8.45-8.57 nm之间;孔道的有序性随表面活性剂与Na2SiO3比例的增大而增加.氮气吸附-脱附等温线为第Ⅳ类型的等温线,在相对压力p/p0=0.15-0.25和P/p0=0.8-1的范围内出现两个H1型滞后环,分别是由介孔孔道和颗粒之间的空穴引起的.BET表面积也随表面活性剂与Na2SiO3比例的增大而增大,最大可达1 100m2/g,最可几孔径在2.20 nm左右.
The cubic structure of mesoporous silica was synthesized by using Germini surfactant [C12H25N + (CH3) 2- (CH2) 2-N + (CH3) 2C12H25] · 2Br- as a template and characterized by small angle X-ray diffraction and nitrogen adsorption- The results show that the obtained mesoporous silica has a cubic structure and the unit cell parameters are between 8.45-8.57 nm. The order of the pores increases with the increase of the ratio of surfactant to Na2SiO3 Increase.The nitrogen adsorption-desorption isotherm is the fourth type of isotherm, there are two H1-type hysteresis rings in the range of relative pressure p / p0 = 0.15-0.25 and P / p0 = 0.8-1, The BET surface area increases with the increase of the ratio of surfactant to Na2SiO3, up to 1 100m2 / g, and the most probable pore diameter is about 2.20 nm.