An organosilane-directed growth-induced etching strategy for preparing hollow/yolk–shell mesoporous organosilica nanospheres with perpendicular mesochannels and amphiphilic frameworks

Abstract

An amphiphilic PMO hollow shell with order mesostructure is constructed for application in sorption and catalysis.

Fe3O4@RGO@Au@C Composite with Magnetic Core and Au Enwrapped in Double-Shelled Carbon: An Excellent Catalyst in the Reduction of Nitroarenes and Suzuki–Miyaura Cross-Coupling

“…4a). The distinct H3 hysteresis loop indicates that the pores in the carbon shell directly open into the hollow interior of double shell, supporting the idea that a guest molecule could quickly diffuse into the hollow space without any obstacle [35]. The BET total surface area of Fe 3 O 4 @RGO@Au@C CDSNs is found to be 221 m 2 g -1 .…”

Facile Synthesis of Yolk/Core-Shell Structured TS-1@Mesosilica Composites for Enhanced Hydroxylation of Phenol

“…Furthermore, the HRTEM images in Figure 2e,f reveal that the mesopores are nearly perpendicular to the microporous frameworks (directed by red arrows) and there are close connections between the mesoporous silica shells and the zeolite cores, facilitating efficient transportation of reactants into active microporous framework through the mesochannels. It is worth mentioning that the current coating process did not involve any surface modifiers or additions that were often necessary for obtaining uniform core-shell structured zeolite@mSiO2 composites with oriented mesochannels in mSiO2 shell [22,23], which can be attributed to the flexibility in current synthesis system [29,30]. In addition, the thickness of mesoporous silica shells could be tailored by adjusting the amount of TEOS precursor.…”

“…The core-shell TS-1@mesosilica composite was prepared via a uniform coating process, according to our previous reports [29,30]. In a typical synthesis, 100 mg of the as-prepared TS-1 zeolite was homogeneously dispersed in a mixture containing 22 mL of water and 11 mL of ethanol by ultrasonication for 30 min.…”

“…The SEM image ( Figure 1a) and TEM image (Figure 2a,b) indicate that the TS-1 sample consist of uniform monodisperse nanocrystals with a particle size of 290-350 nm. Core-shell structured TS-1@mesosilica composites (designated as CS-TS-1@mSiO2−x, x is the thickness of mSiO2 layer) were obtained through a uniform coating process using water-ethanol (2:1), ammonia aqueous, CTAB (hexadecyltrimethylammonium bromide) and TEOS (tetraethylorthosilicate) as solvent, basic catalyst, surfactant and precursor, respectively [29,30]. The SEM micrograph (Figure 1b) shows that the particles are oval in shape with a large diameter (350-400 nm), suggesting that an mSiO2 layer of approximately 30 nm was formed on the surface of the TS-1 crystals.…”

Colloidal Mesoporous Silica Nanoparticles

“…Several groups have reported such a phenomenon, though the mechanism has not been clearly investigated. 269,291 Furthermore, their dispersibilities have not been investigated (may be aggregated). Although this is quite a simple method, the circumstantial conditions for etching silica nanoparticles are still unclear.…”