Synthesis of Ordered Mesoporous Silica with Tunable Morphologies and Pore Sizes via a Nonpolar Solvent-Assisted Stöber Method

Abstract

A facile nonpolar solvent-assisted Stöber method has been developed to synthesize ordered mesoporous silica materials with tunable pore size and diverse morphologies and mesostructures by using cetyltrimethylammonium bromide as the template and tetraethyl orthosilicate as silica precursor in a simple aqueous-phase synthesis system. By simply changing the amount of n -hexane and ammonia–water in the system, ordered mesoporous silica with pore sizes of 2.7–10.5 nm, various morphologies (nanocubes, truncated nanocubes, core–shell microspheres, and twisted nanorods), a high surface area up to 888 m 2 /g, and a large pore volume of 1.55 cm 3 /g are synthesized. Owing to their highly hydrophilic surface, large and accessible pores, and high surface area, the mesoporous silica materials exhibit an excellent performance in adsorption of dye molecules of large dimension (1.6 nm) with a maximum adsorption capacity of 106 mg/g in 10 min at 200 mg/L initial Rhodamine B concentration.