Stable Mesostructured Silicate Films Containing Nanosized Zeolite

Abstract

Evaporation-induced self-assembly via spin coating was employed for the formation of microporous/mesoporous composite films from preformed pure-silica MFI/ethanol and silica/CTABr/ethanol solutions. The thickness of MFI/mesoporous films is in the range of 100−400 nm depending on the different ratios between solutions containing microstructured nanoparticles and the preformed silica/surfactant assemblies forming the final coating suspensions. The structural evolution and crystal orientation of the polycrystalline films were investigated with grazing incidence diffraction (GID) at different penetration depths using synchrotron radiation. Highly ordered mesoporous films showing hexagonal arrangement of the pores and containing MFI nanocrystallites were obtained. Most of the MFI crystals are oriented with their a-axes (sinusoidal channels) perpendicular to the substrates and this orientation is preserved along the film thickness. The porous MFI/mesostructured film, as a function of the penetration depth (ranging from about 7.2 to 250 nm) shows less orientation of the mesostructure in the surface layer.

Ordered Mesoporous Materials Based on Interfacial Assembly and Engineering

“…The common techniques for casting initial solution on the substrate include dip coating,48 spray coating,60 and spin coating,61 etc. Dip coating method is to withdraw the substrate from the coating solution at a certain rate to control the formation of liquid layer on the substrate surface.…”

Functionalized cubic mesostructured silica films

“…The mesophase structure of the as-deposited, calcined and modified films was investigated by GID measurements. The six-circle diffractometer at beam-line ID01 at the ESRF (http://www.esrf.fr) in Grenoble, France was used for all X-ray experiments [15]. The X-ray scattering patterns were recorded with a two-dimensional CCD camera set perpendicular to the incident beam (8 keV).…”

Hierarchically-structured immobilized enzyme displaying the multi-functions of bio-membranes

“…3B) is observed for AAOsilica-enzyme-MNP-3. There have been some reports on the formation of thin films using zeolite or amorphous silica colloids [29][30][31][32] but few 33 involved mesoporous silica nano-particles. The dip-coating of MNPs caused no reduction in the initial protein content (Table 1).…”