Fabrication of centimeter-sized sphere of mesoporous silica with well-defined hollow nanosphere topology and its high performance in adsorbing phenylalanine

Abstract

Large mesoporous silica spheres with centimeter-scale were synthesized for the first time via a multi-level self-assembly using an emulsion system of ethyl ether, tetraethyl orthosilicate (TEOS) and cetyltrimethylammonium bromide (CTAB) surfactant. Apart from the controllable morphology and size, the inorganic hybrid or organic functionalized self-molding mesoporous materials could also be synthesized through one-pot method, that is, the synthesis and functionalization and self-molding with special morphology of the mesoporous material were realized simultaneously. According to the analysis of SEM, TEM, XRD and N 2 adsorption–desorption, the obtained macroscopic spheres were composed of nanosized silica spheres, which possessed relatively ordered mesostructure. Moreover, the obtained macroscopic silica spheres could resist a pressure of 46 N cm −2. The adsorption of phenylalanine was performed to assess the performance of these macrospheres, in which the adsorption capacity of aminopropyl triethoxysilane (APTES) functionalized sample was up to 196 mg g −1, twice higher than the best value reported in the literature.