Generation Of Porous Materials Research Articles

Peptide-based porous materials and their applications

The porous structure formed by the self-assembly of peptides is a new generation of porous materials with potential applications in the fields of catalysis, sensing, separation, and drug delivery. The pores of the material are filled with amino acid side chains, so the pore size and properties of the peptide-based porous material can be adjusted by rational design or modification of the peptide sequences. The introduction of functional moieties and metal ions has expanded the range of peptide-based porous materials. This review covers the design, synthesis, self-assembly, and properties of peptide-based porous materials, and summarizes their applications in different fields in recent years.

Nanocasting Design and Spatially Selective Sulfonation of Polystyrene-Based Polymer Networks as Solid Acid Catalysts.

Nanocasting is a general and widely applied method in the generation of porous materials during which a sacrificial solid template is used as a mold on the nanoscale. Ideally, the resulting structure is the inverse of the template. However, replication is not always as direct as anticipated, so the influences of the degree of pore filling and of potential restructuring processes after removal of the template need to be considered. These apparent limitations give rise to opportunities in the synthesis of poly(styrene-co-divinylbenzene) (PSD) polymer networks of widely varying porosities (BET surface area=63-562 m(2) g(-1) ; Vtot =0.18-1.05 cm(3) g(-1) ) by applying a single synthesis methodology. In addition, spatially selective sulfonation on the nanoscale seems possible. Together, nanocasting and sulfonation enable rational catalyst design. The highly porous nanocast and predominantly surface-sulfonated PSD networks approach the activity of the corresponding molecular catalyst, para-toluenesulfonic acid, and exceed those of commercial ion-exchange polymers in the depolymerization of macromolecular inulin.

Computer Modeling of Nanoporous Materials: An ab initio Novel Approach for Silicon and Carbon

AbstractCarbon and silicon have been consistently proposed as elements useful in the generation of porous materials. Carbon has been insistently postulated as a promising material to store hydrogen, and crystalline silicogermanate zeolites have recently been synthesized and are being considered in catalytic processes. In the present work we report an approach to generating porous materials, in particular porous carbon and silicon, which leads to the existence of nanopores within the bulk. The method consists in constructing a crystalline diamond-like supercell with 216 atoms with a density (volume) close to the real value, then halving the density by doubling the volume (50% porosity), and subjecting the resulting supercell to an ab initio molecular dynamics process at 300 K for Si, and 1000 K for carbon, followed by geometry relaxation. The resulting samples are essentially amorphous and display pores along some of the “crystallographic” directions. We report their radial distribution functions and the pore structure where prominent.