Material Characterization Study of Magnetite Nanocrystals for RF Sensing.

Magnetite nanocrystals show promise for electrically small gigahertz frequency applications, which could lead to miniaturizing transformer cores and new sensing technologies. This work presents a rigorous radiofrequency characterization of these nanocrystals using vector network analyzer (VNA) ferromagnetic resonance (FMR) measurements. For the first time, two different average diameters of FeO nanocrystals are investigated (7.

Templated synthesis enhances the cobalt adsorption capacity of a porous organic polymer.

Divalent transition metals such as Co(II) are important targets for removal from water sources, due to their potential toxicity as well as their high value. In this study, we found that a series of porous organic polymers based on amide-linked tetraphenylmethane units are effective Co(II) ion adsorbents in aqueous solution. To increase the density of Co(II) binding sites, we then developed a templated synthesis in which the branched, rigid monomers are pre-assembled around Co(II) ions prior to polymerization.

Radicals Are Required for Thiol Etching of Gold Particles.

Etching of gold with an excess of thiol ligand is used in both synthesis and analysis of gold particles. Mechanistically, the process of etching gold with excess thiol is unclear. Previous studies have obliquely considered the role of oxygen in thiolate etching of gold.

Oxidative decomposition of Au25(SR)18 clusters in a catalytic context.

Gold nanoparticle catalysis of chemical transformations has emerged as a subject of intense interest over the past decade. In particular, Au25(SR)18 has emerged as a model catalyst. In an effort to investigate their potential as intact, homogeneous, unsupported catalysts, we have discovered that Au25(SR)18 clusters are not stable in oxidizing conditions reported for catalytic styrene oxidation.