物理化学学报 >> 2010, Vol. 26 >> Issue (02): 515-520.doi: 10.3866/PKU.WHXB20100211

材料物理化学 上一篇    下一篇

PW11/SBA-15介孔杂化材料的直接合成与表征

王金娥, 杨春   

  1. 南京师范大学化学与环境科学学院, 江苏省生物功能材料重点实验室, 南京 210097
  • 收稿日期:2009-09-04 修回日期:2009-10-26 发布日期:2010-01-26
  • 通讯作者: 杨春 E-mail:yangchun@njnu.edu.cn

Direct Syntheses and Characterizations of PW11/SBA-15 Mesoporous Hybrid Materials

WANG Jin-E, YANG Chun   

  1. Jiangsu Key Laboratory of Biofunctional Materials, College of Chemistry and Environmental Science, Nanjing Normal University, Nanjing 210097, P. R. China
  • Received:2009-09-04 Revised:2009-10-26 Published:2010-01-26
  • Contact: YANG Chun E-mail:yangchun@njnu.edu.cn

摘要:

采用三嵌段共聚物EO20PO70EO20 (P123)为模板剂, 正硅酸乙酯(TEOS)和缺位Keggin型多金属氧酸盐Na7PW11O39 (PW11)为无机前驱体, 由共缩合法一步合成了PW11/SBA-15 介孔杂化材料. 通过红外(IR)光谱、紫外-可见漫反射光谱(UV-Vis/DRS)、X射线衍射(XRD)、低温N2吸附、透射电子显微镜(TEM)等手段对杂化材料和合成过程进行了表征. 结果表明: 杂化材料中不仅多金属氧酸盐的Keggin单元保留完整, 且共价键联于介孔孔道内部, 而且样品基本具有规整有序的六方介孔结构. TEOS预水解时间的长短对有序结构的构筑有明显影响, 随预水解时间延长, 样品的介观有序性增加. 这是因为多金属氧酸盐对模板剂P123有盐析作用, 其作用大小与多金属氧酸盐前驱物的溶解度有关.

关键词: 介孔分子筛, 多金属氧酸盐, 杂化材料, Na7PW11O39, SBA-15

Abstract:

The hybrid mesoporous materials, PW11/SBA-15, were synthesized using tetraethoxysilane (TEOS) and lacunary polyoxometalate Na7PW11O39 (PW11) by a co-condensation approach in the presence of triblock copolymer EO20PO70EO20 (P123) as a template. The resultant materials were characterized by infrared (IR) spectroscopy, UV-Vis diffuse reflectance spectroscopy (UV-Vis/DRS), powder X-ray diffraction (XRD), N2 adsorption-desorption, and transmission electronmicroscopy (TEM). Results show that the Keggin units are retained perfectly and grafted onto the pore walls of the mesoporous silica by covalent linkage, and an ordered hexagonal packing of channels with homogeneous pore diameters is obtained in the materials. The prehydrolysis time of TEOS influences the construction of the ordered mesostructure significantly. The long-range ordered mesophase increases as the prehydrolysis time increases because of the salt-out effect of PW11, which is associated with solubility of the polyoxometalate precursors.

Key words: Mesoporous molecular sieve, Polyoxometalate, Hybrid materials, Na7PW11O39, SBA-15

MSC2000: 

  • O643