Generating Isotropic Superparamagnetic Interconnectivity for the Two-Dimensional Organization of Nanostructured Building Blocks

Antioxidant Potential and Toxicity Study of the Cerium Oxide Nanoparticles Synthesized by Microwave-Mediated Synthesis

Monodispersed cerium oxide nanoparticle has been synthesized by microwave-mediated hydrothermal as well as microwave-mediated solvothermal synthesis. X-ray diffraction (XRD) data shows that the synthesized particles are single phase. SEM and TEM analysis suggest that particle synthesized by microwave-mediated solvothermal method are less agglomerated. In vitro toxicology study of the synthesized nanoceria particles has shown good free radical scavenging activity for NO and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical assayed except superoxide radical within a concentration range of 25 to 75 ng ml(-1). Nanoceria particle also showed inhibition of Fe-ascorbate-induced lipid peroxidation (LPx) in chick liver mitochondrial fractions. Solvothermally synthesized nanoceria showed better protection against Fe-ascorbate-induced LPx than the hydrothermal one while the hydrothermally synthesized nanoceria showed better DPPH and NO scavenging activity. The ceria nanoparticles also prevented Fe-ascorbate-H2O2-induced carbonylation of bovine serum albumin in a dose-dependent manner. At higher concentration, i.e., 100 ng ml(-1), the synthesized nanoparticles showed a reverse trend in all the parameters measured indicating its toxicity at higher doses.

Microbial synthesis of multishaped gold nanostructures

The development of methodologies for the synthesis of nanoparticles of well-defined size and shape is a challenging one and constitutes an important area of research in nanotechnology. This Full Paper describes the controlled synthesis of multishaped gold nanoparticles at room temperature utilizing a simple, green chemical method by the interaction of chloroauric acid (HAuCl4 x 3H20) and cell-free extract of the fungal strain Rhizopus oryzae. The cell-free extract functions as a reducing, shape-directing, as well as stabilizing, agent. Different shapes of gold nanocrystals, for example, triangular, hexagonal, pentagonal, spherical, spheroidal, urchinlike, two-dimensional nanowires, and nanorods, are generated by manipulating key growth parameters, such as gold ion concentration, solution pH, and reaction time. The synthesized nanostructures are characterized by UV/Vis and Fourier-transform infrared spectroscopy, transmission electron microscopy, and energy dispersive X-ray analysis studies. Electron diffraction patterns reveal the crystalline nature of the nanoparticles and a probable mechanism is proposed for the formation of the different structural entities.

Ionic-liquid-assisted sonochemical synthesis of carbon-nanotube-based nanohybrids: control in the structures and interfacial characteristics

A versatile, facile, and rapid synthetic method of advanced carbon nanotube (CNT)-based nanohybrid fabrication, or the so-called ionic-liquid-assisted sonochemical method (ILASM), which combines the supramolecular chemistry between ionic liquids (ILs) and CNTs with sonochemistry for the control in the size and amount of uniformly decorated nanoparticles (NPs) and interfacial engineering, is reported. The excellence in electrocatalysis of hybrid materials with well-designed nanostructures and favorable interfaces is demonstrated by applying them to electrochemical catalysis. The synthetic method discussed in this report has an important and immediate impact not only on the design and synthesis of functional hybrid nanomaterials by supramolecular chemistry and sonochemistry but also on applications of the same into electrochemical devices such as sensors, fuel cells, solar cells, actuators, batteries, and capacitors.

Hollow single-crystal spinel nanocubes: the case of zinc cobalt oxide grown by a unique Kirkendall effect

Small hollow nanocubes of the ternary spinel Zn x Co 1- x Co 2O 4 of ca. 18 nm dimension were prepared via a facile hydrothermal route. A growth mechanism is suggested in which solid single-crystal Co 3O 4 nanocubes are gradually converted to hollow single-crystal Zn x Co 1- x Co 2O 4 nanocubes with preservation of the spinel framework through differential diffusion of Zn (2+) and Co (2+) ions. With the cation exchange, the chemical composition and thus physical properties can be tailored.

Monodisperse nanocrystals: general synthesis, assembly, and their applications

This article summarizes the recent advances in the synthesis, assembly and applications of monodisperse nanocrystals, which may be suggestive for the designed synthesis and assemblies of target nanocrystals according to practical requirements.

Self-assembly of uniform hexagonal yttrium phosphate nanocrystals

We report a facile chemical route for the synthesis of uniform hexagonal yttrium phosphate hydrate nanocrystals and their assembly into close-packed regular superstructures through noncovalent interactions of long chain molecules attached to the surfaces of inorganic nanocrystals.