Synthesis and characterization of highly ordered bifunctional aromatic periodic mesoporous organosilicas with different pore sizes

Abstract

The first syntheses of highly ordered bifunctional periodic mesoporous organosilicas (PMOs) containing different amounts of aromatic thiophene and benzene bridging groups are reported. Employing the triblock copolymer Pluronic P123 as well as the oligomeric Brij 76 surfactant under acidic conditions as supramolecular structure-directing agents, the syntheses of two series of bifunctional aromatic PMO materials with pore sizes in the range of 4.8–5.4 and 3.3 nm, respectively, have been realized. Independent of the molar ratios of the organosilanes in the initial reaction mixtures, highly ordered PMO materials with 2D hexagonal mesostructures have been obtained in all cases. After a one-off calibration based on ²⁹Si MAS NMR measurements, the quantification of the organic functional groups has been carried out for the first time, in case of PMO materials, using Raman spectroscopic methods.