| Abstract
| - Mesoporous silica with squared one-dimensional channels (KSW-2-type mesoporous silica),possessing a molecularly ordered framework arising from a starting layered polysilicate kanemite, wasobtained through silylation of a surfactant (hexadecyltrimethylammonium, C16TMA)-containing mesostructured precursor with octoxytrichlorosilane (C8H17OSiCl3) and octylmethyldichlorosilane (C8H17(CH3)SiCl2).The presence of the molecular ordering in the silicate framework was confirmed by XRD and TEM. Octoxygroups grafted on KSW-2 can be eliminated by subsequent hydrolysis under very mild condition, and puremesoporous silica was obtained with the retention of the kanemite-based framework. The framework isstructurally stabilized by the attachment of additional SiO4 units to the framework, and the mesostructuralordering hardly changed under the presence of water vapor. A large number of silanol groups remained atthe mesopore surfaces because C16TMA ions and octoxy groups can be removed without calcination.Octylmethylsilyl groups are regularly arranged at the mesopore surface due to the molecular ordering inthe silicate framework. The molecularly ordered structural periodicity originating from kanemite is retainedeven after calcination at 550 °C, while that in the precursor without silylation disappeared. The syntheticstrategy is quite useful for the design of the silicate framework of mesostructured and mesoporous materialswith and without surface functional organic groups.
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