The synthesis and solution and solid-state structural characterization of a family of amine bis(phenolate) [ONNO]-vanadium complexes is reviewed. These compounds have oxi dation states ranging from vanadium(II) to vanadium(V), and were evaluated as olefin polymerization catalysts. In association with EtAlCl2 cocatalyst, we studied the homo polymerization of ethylene, propene, and 1-hexene, as w...

We report the observation of a magnetic moment on vanadium embedded in copper. Using x-ray-absorption spectroscopy and x-ray magnetic circular dichroism we show that the vanadium atomic magnetic moment is strongly dependent on the formation temperature of the VCu alloy. The absorption spectra allow us to distinguish the electronic transitions which are the signature of the magnetic state from t...

The present research investigated the sol–gel preparation, dielectric and ferroelectric properties of PZT films doped with 5 mol% vanadium oxide. Stable PZTV sols can be readily formed, and homogeneous, micrometer thick and pinhole-free PZTV films were obtained by using spin coating followed with rapid annealing. The X-ray diffraction patterns revealed that no parasitic or secondary phases were...

FeCo nanoparticles (4 ± 1 nm), encapsulated by SiO2, were synthesized with and without a 2% (atomic ratio) vanadium doping. The impact from the presence of vanadium, an additive often used in the bulk to alter both physical and mechanical properties, on the nanomagnetism was probed by element-specific X-ray spectroscopy and magnetometry techniques. While the nanostructure was unaffected by the ...

Vanadium is found in many rocks and minerals, including asphaltite. Asphaltite is one of the naturally occurring black, solid bitumens, which are soluble at heating in carbon disulfide and fuse. Asphaltite is also a solidified hydrocarbon compound derived from petroleum. Determination of vanadium in asphaltite ash was performed by microwave-acid digestion followed by inductively coupled plasma-...

Vanadium-doped ZnSe films were epitaxially grown on (100) GaAs substrates by metal-organic vapor phase epitaxy. The crystal structure and the state of vanadium in the ZnSe crystal were investigated using X-ray diffractometry, infrared absorption, and photocurrent. It was revealed that zinc sites in the ZnSe crystal were substituted by vanadium atoms on the basis of the results of infrared absor...

The title compound was hydrothermally synthesized from elemental vanadium, phosphoric and boric acids, and ethylenediamine. It is isostructural with the mixed-valence titanium phosphate TiTi(HPO4)4?enH?H2O (TPO-2) but differs in electronic states and in its magnetic properties. The structure [tetragonal, I41, a ~ 6.3881(4) and c ~ 16.608(1) Å] is of the open-framework type and is composed of co...

Although the rechargeable lithium-sulfur battery is an advanced energy storage system, its practical implementation has been impeded by many issues, in particular the shuttle effect causing rapid capacity fade and low Coulombic efficiency. Herein, we report a conductive porous vanadium nitride nanoribbon/graphene composite accommodating the catholyte as the cathode of a lithium-sulfur battery. ...

The all-vanadium redox fl ow battery is a promising technology for large-scale renewable and grid energy storage, but is limited by the low energy density and poor stability of the vanadium electrolyte solutions. A new vanadium redox fl ow battery with a signifi cant improvement over the current technology is reported in this paper. This battery uses sulfate-chloride mixed electrolytes, which a...

The study of the effects exerted by vanadium on living systems has recently became an object of growing interest. In fact, the possibility to develop vanadium as a new drug in the treatment of diabetes and cancer calls for the individuation of the cellular vanadate-sensitive targets. Moreover, the fact that vanadium can be an environmental pollutant in urban and industrial areas, as a consequen...