溶胶凝胶法制备FexOy／SBA-15介孔分子筛及磁性能研究  

Preparation and Magnetic Properties of Fe_xO_y/SBA-15 Molecular Sieves through Sol-Gel Method

作　　者：王新庆[1] 葛洪良[1] 金红晓[1] 李良[1] 卫国英[1] 

机构地区：[1]中国计量学院材料科学与工程学院浙江省磁学重点实验室,物理系,浙江杭州310018

出　　处：《稀有金属材料与工程》2008年第A02期659-662,共4页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(10647149,20571067,20601024)资助

摘　　要：SBA-15介孔分子筛具有较大的孔径及优异的水热稳定性,在其中掺杂其它材料可以保证掺杂材料良好的分散性,使晶粒尺寸在纳米量级,呈现新的性能。本文利用溶胶-凝胶法及水热法在酸性的条件下两步直接合成SBA-15及FexOy/SBA-15介孔分子筛磁性材料,进而利用X射线粉末衍射(XRD)、透射电子显微镜(TEM)以及场发射扫描电子显微镜(FESEM)对制备的FexOy/SBA-15介孔分子筛的结构以及形貌进行分析、表征。另外,利用振动样品磁强计(VSM)研究了煅烧温度对FexOy/SBA-15介孔分子筛材料的磁学性能的影响,结果显示,FexOy/SBA-15介孔分子筛材料的矫顽力以及比饱和磁化强度随着煅烧温度的增加而先增加后减小,在煅烧温度为850℃时,达到最大值:Hc=31044A/m及σs=0.22A.m2.kg-1。With the large mesopores and the excellent hydrothermal stability, the doped SBA-15 molecular sieves have presented the unique properties, which could make the doped materials disperse well in SBA-15 molecular sieves and exit in nanoparticles. In this paper, the sol-gol method and the hydro-thermal method were used to prepare SBA-15 and FexOy/SBA-15 mesoporous molecular sieves in the acid condition by two-step process. X-ray powder diffraction （XRD）, transmission electron microscopy （TEM） and field emission scanning electron microscopy （FESEM） were carried out to characterize and analyze the microstructure and morphology of the as-prepared FexOy/SBA-15 molecular sieves. Furthermore, the magnetic properties of the as-prepared FexOy/SBA- 15 molecular sieves were measured by the vibrating sample magnetometer （VSM）. The results indicate that when T〈850 ℃, the magnetic properties increases with the increasing of the calcined temperature, and decreases with the increasing of the calcined temperature when T〉850℃. The optimal magnetic properties is the coercive force of He=31044 A/m and the specific saturated magnetization of σs=0.22A·2.kg^-1 at the calcined temperature of 850 ℃.

关 键 词：溶胶-凝胶法 SBA-15介孔分子筛 磁性能 

分 类 号：O482.5[理学—固体物理]