Microstructural and mechanical properties of organic surfactant templated nanoporous thin silica films have been studied by X-ray diffraction, Fourier transform infrared spectroscopy, and nanoindentation. Compared with many other porous low-k dielectrics, the self-assembled molecularly templated nanoporous silica films demonstrate better mechanical properties. This is ascribed to the presence o...

Low refractive index thin films have generated substantial interest for use in optical devices particularly in Light Emitting Diodes (LEDs). Applications include photonic cavities, mirrors, etc. Such films are required to have precise control over both thickness and refractive index. Here, we investigate fabrication of Omni Directional Reflectors (ODRs) using nanoporous silica films. Sub-100 nm...

Using sum-frequency vibrational spectroscopy, we found that water structure at nanoporous silica/water interfaces depended on the nanoporous film structure. For a periodic, self-assembled nanoporous film with monosized 2 nm pores occupying 20% of the top surface area, the surface vibrational spectrum was dominated by water in contact with silica, bare or covered by silane, at the top surface. I...

Recently discovered synthesis of unusual curved nanoporous silica shapes, such as rods, discoids, spheres, tubes, and hollow helicoids, have brought forth the problem of understanding the formation mechanism. Knowledge of such mechanism may lead to the ability to control the nanoporous shapes. This is important in a variety of applications and new technologies where nanostructure and geometry d...

Ordered nanoporous silicas containing various binary copper-manganese oxides were prepared as catalytic systems for effective carbon monoxide elimination. The carbon monoxide elimination efficiency was demonstrated as a function of the [Mn]/[Cu] ratio and reaction time. The prepared catalysts were characterized by Brunauer-Emmett-Teller (BET) method, small- and wide-angle X-ray diffraction (XRD...

A facile spray drying technique has been developed for large-scale and template-free production of nanoporous silica with controlled morphology, large pore size, and high pore volume, using commercially available fumed silica, Aerosil 200, as a sole precursor. This approach can be applied to the preparation of functional nanoporous materials, in this study, lanthanum oxide functionalised silica...

knoevenagel condensation between barbituric acid and aldehyde was investigated in the presence of sulfonic acid functionalized nanoporous silica (sba-pr-so3h) and resulted in the formation of arylidene and bis-arylidene barbiturates. excellent yields and short reaction times are related to the high efficiency of sba-pr-so3h that the reactions take place easily in its nano-pores. sba-pr-so3h as ...

The goal of the present study was to compare the drug release properties and stability of the nanoporous silica with different pore architectures as a matrix for improved delivery of poorly soluble drugs. For this purpose, three dimensional ordered macroporous (3DOM) silica with 3D continuous and interconnected macropores of different sizes (200 nm and 500 nm) and classic mesoporous silica (ie,...

Nanostructured porous silica coatings were synthesized on titanium by the combined sol-gel and evaporation-induced self-assembly process. The silica-coating structures were characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and nitrogen sorptometry. The effect of the nanoporous surface on apatite formation in simulated body fluid, protein adsorpt...

Highly selective porous films were prepared by spin-coating deposition of colloidal silica nanoparticles on an appropriate macroporous substrate. Silica nanoparticles very homogenous in size were obtained by sol-gel reaction of a metal oxide silica precursor, tetraethyl orthosilicate (TEOS), and using polystyrene-block-poly(ethylene oxide) (PS-b-PEO) copolymers as soft-templating agents. Nanopa...