Fabrication and characterisation of Fe2O3/chitosan aerogel-like spheres

Presently, biopolymer materials have been given more attention for their outstanding properties, high efficiencies and promising applications in various fields. In this study, Fe2O3/chitosan aerogel-like spheres were successfully prepared from chitosan and FeCl3 by sol–gel process and freeze-drying to provide high-surface area materials. The factors affecting the material synthesis have been studied. The asprepared Fe2O3/chitosan material was characterized by Infrared Spectroscopy (IR), X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) methods. The results showed that the aerogel spheres have a hollow structure made of chitosan nanofibril networks. Fe2O3 nanoparticles get high crystallinity and have an average particle size of 33 nm.

Application of novel nanomagnetic metal–organic frameworks as a catalyst for the synthesis of new pyridines and 1,4-dihydropyridines via a cooperative vinylogous anomeric based oxidation

Herein, a new magnetic metal–organic frameworks based on Fe3O4 (NMMOFs) with porous and high surface area materials were synthesized. Then, NMMOFs were characterized by FT-IR, XRD, SEM, elemental mapping, energy dispersive X-ray (EDS), TG, DTG, VSM, and N2 adsorption–desorption isotherms (BET). Fe3O4@Co(BDC)-NH2 as a magnetic porous catalyst was applied for synthesis of novel fused pyridines and 1,4-dihydropyridines with pyrazole and pyrimidine moieties as suitable drug candidates under ultrasonic irradiation. The significant advantages of the presented methodology are mild, facile workup, high yields, short reaction times, high thermal stability, and reusability of the described NMMOFs catalyst.

Nanostructured TiO2 Materials: Preparation, Properties and Potential Applications (3P’s)

Nanostructured materials are a new class of materials which provide one of the greatest potentials for improving performance and extended capabilities of products in a number of applications. In particular nanostructured TiO2 was used as photocatalysts, gas sensor, solar cells and nanocomposite biomaterials. For each of these applications, aspects such as surface morphology, crystallinity and chemistry of the titania-based materials are the key parameters to be settled for the process optimization. A series of nanostructured TiO2 materials (TiO2 nanotubes, TiO2 nanorods, TiO2 nanoparticles) was synthesized using simple hydrothermal methods. X-Ray Diffraction (XRD), Field Emission Scanning Electron microscope (FESEM) and Brunauer–Emmett–Teller (BET) surface area characterization was carried out to study the properties of synthesized nanostructured TiO2 materials. The performance of synthesized nanostructured TiO2 was evaluated for various applications such as photocatalyst for methyl orange (MO) degradation and anti-bacterial thin film for biomedical and food packaging. Among the nanostructured TiO2 materials, TiO2 nanotubes shows the highest activity regardless of their applications. This is probably due to their nanotubular morphology in which provided high surface area materials. The surface area of TiO2 nanotubes was found to be 226.52 m2/g. The outer and inner diameters of nanotubes are 4 nm and 10 nm, respectively with several hundred nanometers in length. Anatase TiO2 phase structure and crystallinity of TiO2 nanotubes supports the good performances of the nanostructured materials.

Particulate Release From Nanoparticle-Loaded Shape Memory Polymer Foams

Highly porous, open-celled shape memory polymer (SMP) foams are being developed for a number of vascular occlusion devices. Applications include abdominal aortic and neurovascular aneurysm or peripheral vascular occlusion. A major concern with implanting these high surface area materials in the vasculature is the potential to generate unacceptable particulate burden, in terms of number, size, and composition. This study demonstrates that particulate numbers and sizes in SMP foams are in compliance with limits stated by the most relevant standard and guidance documents. Particulates were quantified in SMP foams as made, postreticulation, and after incorporating nanoparticles intended to increase material toughness and improve radiopacity. When concentrated particulate treatments were administered to fibroblasts, they exhibited high cell viability (100%). These results demonstrate that the SMP foams do not induce an unacceptable level of risk to potential vascular occlusion devices due to particulate generation.

Isoreticular expansion of polyMOFs achieves high surface area materials

Polymer–MOF hybrid materials (polyMOFs) are shown to adhere to the principle of isoreticular expansion, generating polyMOFs with large surface areas and enhanced stability.

The Synthesis of High-Surface Area Silicon Carbide by Conversion Method Using Carbosilane Polymer

Since mesoporous silica such as MCM-41 and SBA-15 was developed, the study of the properties of high-surface area materials was accelerated. Moreover, the mesoporous silica is used as a template to produce high-surface materials by nanocasting technology. The purpose of this paper is the synthesis of a high surface silicon carbide sphere by the nanocasting technology. In this study, KCC-1 silica sphere was used as a template, and polycarbosilane and poly (phenyl carbosilane) were selected for precursor of silicon carbide. Carbosilane polymer gives advantage of synthesis silicon carbide under low temperature, and hollow spheres were produced. In this study, the polycarbosilane was more effective for the synthesis of SiC hollow spheres by inversion of template structure showing a fibrous morphology on the sphere wall. And it was confirmed that the sphere was composed of nanosized SiC crystals, and has high surface area using TEM, XRD and BET analysis.