表面活性剂对二氧化硅空心微球结构的影响

Effect of surfactant on structure of silica hollow microspheres

分别在阳离子和阴离子两种不同类型表面活性剂的存在下,用正硅酸乙酯(TEOS)为硅源包覆纳米尺度的碳酸钙颗粒,去除表面活性剂和碳酸钙,得到了二氧化硅空心微球。用TEM、XRD及低温氮吸附等测试手段对这类材料进行了表征,研究了表面活性剂对样品结构的影响。结果表明,在合成中加入表面活性剂,使二氧化硅空心微球的球壳上出现了介孔相,改善了样品的孔结构。空心微球的BET比表面积为399～898m2/g,明显高于未加表面活性剂的样品。

The silica hollow microspheres was prepared by using CaCO3 nanoparticles as core template and TEOS as silica source. Cationic surfactant and anionic surfactant were used in the synthesis. TEM, XRD and nitrogen adsorption were employed to characterize the prepared materials and the effects of the surfactants on the structure of the materials were analyzed. Experimental results indicated the walls of the as-prepared materials displayed mesopores characteristics, which meant both surfactants could improve the structure of the hollow microspheres. Meanwhile, the BET surface areas of the samples produced by using the surfactants were 399-898 m2/g, which were much higher than that of the sample without surfactant in it.