Direct Synthesis of Bifunctionalized Hexagonal Mesoporous Silicas and Its Catalytic Performance for Aerobic Oxidation of Cyclohexane

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• 作者：Chen Chen ; Jie Xu* ; Qiaohong Zhang ; Hong Ma ; Hong Miao ; Lipeng Zhou
• 刊名：Journal of Physical Chemistry C
• 出版年：2009
• 出版时间：February 19, 2009
• 年：2009
• 卷：113
• 期：7
• 页码：2855-2860
• 全文大小：211K
• 年卷期：v.113,no.7(February 19, 2009)
• ISSN：1932-7455

文摘

According to the characteristics of the cyclohexane oxidation reaction a series of bifunctionalized hexagonal mesoporous silicas, CoPh-HMS, were designed and successfully synthesized by a one-step co-condensation route. The results of small-angle XRD, TEM, and N₂ adsorption−desorption measurements showed that the resultant materials had well-ordered mesoscopic structures. Co²⁺ ions were incorporated into the frameworks in tetrahedral coordination along with phenyl groups immobilized on the surface, confirmed by a careful spectroscopic (FT-IR, UV−visible, and ²⁹Si MAS NMR) study. The surfaces of the materials were proved to be more hydrophobic with higher Ph loading, and the largest water droplet contact angle is up to 110.50°. These materials were applied in the liquid-phase oxidation of cyclohexane with molecular oxygen as oxidant and tert-butyl hydroperoxide as initiator under solvent-free conditions. High activity could be obtained with these bifunctionalized catalysts being used. The modification effect of phenyl groups played an important role in the activity enhancement.