Functional mesoporous material derived from 3D net-linked SBA-15.

A novel, versatile functional mesoporous material with the structure of SBA-15 but a specific 3D net-linked morphology has been prepared by using a facile method. This material has been assessed for its ability to reduce the level of nitrosamines in tobacco smoke so that the actual effect of this material in the reduction of carcinogenic environmental pollutants in a complex chemical system can be verified. By adjusting the force field during the hydrolysis and condensation processes of tetramethyl orthosilicate (TMOS) in an aqueous reaction system, the SBA-15 silica, which has a special morphology in that it is long and fiberlike from a microscopic view but large and block-like from a macroscopic angle, has been successfully synthesized. Moreover, the synthetic product is no longer a powder but a block because of its specific 3D net-linked morphology, which enables the material not only to trap particles in smoke but also to potentially be applied as a device. To strengthen the adsorptive capability of this porous material, a dry-impregnation procedure was applied in which zirconia was coated on the silica wall without changing the morphology. As expected, this functional material shows a high activity in the adsorption of N'-nitrosonornicotine (NNN), a bulky tobacco-specific nitrosamine, in solution and of N-nitrosopyrrolidine (NPYR), a volatile nitrosamine, in the gas stream. Furthermore, this 3D net-linked SBA-15 material can efficiently decrease the amount of nitrosamines and total number of particles in mainstream smoke when it is tested as an additive in the filter of a cigarette, thus providing powerful protection for the environment and public health.