Organosilica hexagonal

Then, we attempted to prepare a 2D hexagonal mesoporous organosilica thin film containing 1 in the channel pores and an erbium complex 5Er (the synthesis of which was previously described [17]) in the framework (Scheme 3). 

Mixed micelles can be exploited as templates for preparation of nanoporous materials. Oligomeric alkyl-ethylene oxide surfactant (Polyoxyethylene (2) cetyl ether, B52), and ionic surfactant (cetyltrimethylammonium bromide, CTAB) form mixed micelles that self-assemble into well-ordered hexagonal and bimodal mesostructures. These systems can be used as templates to synthesize hydrothermally stable organized periodic mesoporous organosilicas (PMOs). The X-ray diffraction (XRD), TEM, BET, NMR and hydrothermal studies have been used to investigate the effects of B52 on the formation of various PMOs. The addition of B52 in the surfactant solution improves... 

Ternary phase diagrams were obtained for partial and complete miscibility between the solvent and the silica or organosilica precursor at the reduced temperature r =8.0. In some cases, a liquid crystal phase with high surfactant concentration is at equilibrium with a solvent-rich phase containing a small fi action of free monomers or micelles. Hexagonal phases are obtained for surfactant volume fractions between 50% and 70%, whereas lamellar... 

As shown in Scheme 4.4, an organosilica that showed pore structure with 2D hexagonal symmetry was obtained upon hydrolysis-condensation of the disUy-lated organic precursor in the presence of a surfactant as a structure-directing agent. Cationic or neutral surfectants were used to generate mesoporous material. 

Small angle X-ray diffractograms of the organosilica material (A16A18) with 2D hexagonal symmetry... 

G. A. (1999) Periodic mesoporous organosilicas, PMOs fusion of organic and inorganic chemistry inside the channel walls of hexagonal mesoporous silica. Chem. Commun., (24), 2539-2540 ... 

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