FexOy/SBA-15介孔分子筛的合成以及性能研究

在酸性溶液中利用溶胶凝胶-pH值控制两步法直接合成Fe_xO_y/SBA-15介孔分子筛，同时利用场发射扫描电子显微镜(FESEM)、小角度X射线衍射(Low-angle XRD)、透射电子显微镜(TEM)以及振动样品磁强计(VSM)对制备的各种SBA-15介孔分子筛进行结构以及性能的测试、表征。结果显示Fe_xO_y均匀地分散在SBA-15的骨架中，而且会对SBA-15介孔分子筛起钉轧作用。而后着重研究了Fe_xO_y的加入对SBA-15介孔分子筛的热稳定性、催化特性以及磁学性能的影响。Fe_xO_y的引入可以增加制备的SBA-15介孔分子筛的热稳定性;Fe_xO_y的引入可以改善SBA-15介孔分子筛的催化活性，得到了开口的、石墨化程度较好的纳米碳管。Fe_xO_y的引入使SBA-15介孔分子筛具有明显的铁磁性。

Synthesis and Performance of FexOy-doped SBA-15 Mesoporous Molecular Sieves

FexOy/SBA-15 mesoporous molecular sieves were prepared in acid solution with the sol-gel method and hydrothermal method. The microstructure and properties of the as-prepared FexOy/SBA-15 molecular sieves were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM) and vibrating sample magnetometer (VSM). The effect of the calcination temperature on the stability of the FexOy/SBA-15 mesoporous molecular sieves was discussed, and the results show that the addition of FexOy could improve the thermal stability of the FexOy/SBA-15 mesoporous molecular sieves to some extent. All results suggest that the FexOy nanoparticles are well-dispersed in the frame of SBA-15 molecular sieves and act as the anchor, preventing the shrinkage of the mesopores. The influence of the addition of FexOy on the catalysis and the magnetic properties was also discussed. Opened multi-walled carbon nanotubes with well-graphitization were obtained using this material as catalyst by catalytic chemical vapor deposition method. Furthermore, the as-prepared FexOy /SBA-15 molecular sieves presented the ferromagnetic properties obviously.