Bridged amine-functionalized mesoporous organosilica materials from 1,2-bis(triethoxysilyl)ethane and bis[(3-trimethoxysilyl)propyl]amine

Amine-functionalized, organic/inorganic hybrid mesostructured organosilica (BAFMO) materials have been synthesized and characterized from two bridged silsesquioxane precursors, 1,2-bis(triethoxysilyl)ethane (BTESE) and bis(3-trimethoxysilyl)propyl]amine (BTMSPA). Mole ratios of BTESE ranged from 0.05, 0.10, 0.125, to 0.175. The synthetic pathway involves employing cetyltrimethylammonium bromide as a template under basic conditions at room temperature. X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies revealed that the resultant BAFMO materials possess mesocopically ordered, hexagonal symmetries and well-defined morphologies. However, the order was decreased as the amount of BTMSPA increased, in terms of the d₁₀₀ spacings and the unit cell parameters on XRD as well as the TEM images. N₂ gas sorption experiments showed a gradual decrease in both the surface area, from 1075 to 688 m²/g, and the pore volume, from 2.08 to 0.55 cm³/g, on increasing the amount of BTMSPA. The organic functionalization was successfully determined by Fourier-transform infrared and ¹³C CP MAS NMR spectroscopy. X-ray photoelectron spectroscopy and elemental analysis results also confirmed the presence of Si-C bond as well as amine functionalities in the solvent-extracted mesoporous organosilica materials.