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

Abstract

A facile nonpolar solvent-assisted Stober 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.

Hierarchical Mesoporous Organosilica–Silica Core–Shell Nanoparticles Capable of Controlled Fungicide Release

“…As revealed by materials HSMSCSN‐ n , during the process of formation of the n ‐hexane‐assisted uniform core–shell structures, the pore size of the shell layer can be enlarged to a maximum of 5.9 nm (Table ). This can be interpreted by n ‐hexane acting as a swelling agent, since it can readily diffuse into the hydrophobic core of the CTAB micelle and thereby expand the micelle size, aided by the stirring during shell formation . Moreover, TEOS dissolved in n ‐hexane can also be adsorbed into the core of CTAB micelles by hydrophobic interactions .…”

“…The PXRD pattern of Me‐HSMSCSNs shows a series of well‐resolved diffraction peaks in the 2 θ range of 1.4–4.5°, which can be indexed as the (210), (211), (321), (400), (420), and (422) reflections of the cubic Pm n space group, arising from the PMO core structure (cf. Me‐PMO, Figure S18 of the Supporting Information) . The (100) plane indicated by the peak/shoulder at 2 θ =1.495° may represent a distorted hexagonal p 6 mm symmetry of the shell layer with large pore size (Figure c).…”

“…Apart from MSCSNs, mesoporous carbon and titania microspheres also exhibit great potential for applications in energy conversion and sensing . Recently, hierarchically structured mesoporous silica‐based core–shell nanoparticles have become an emerging field . Different core–shell pore sizes, uniformly distributed over the entire nanoparticle, are proposed to create a unique nanosystem for further‐reaching applications in the aforementioned areas.…”

“…Such multistep syntheses are promising in controlling the core and shell properties, but are considered tedious and not easy to handle. Hence, a simple procedure for the fabrication of MSCSNs, ideally a one‐pot synthesis, seems more attractive …”

Mesoporous metallic rhodium nanoparticles

“…Making mesoporous frameworks composed of carbon4567, metal oxides89, silica10111213, polymers141516 and metals171819 has led to enhanced performance in catalysis2021, energy conversion and storage2223, surface-enhanced Raman spectroscopy (SERS)2425 and chemical/biochemical sensing26. In particular, the application of mesoporous noble metals in the field of heterogeneous catalysis has distinct and numerous advantages in terms of performance.…”