Effect of structural parameters on electrical properties of vanadate layers
Vanadium creates systems with varied electrochemical properties due to its ability to form various oxidation states (II-V). Vanadium-containing systems can be widely utilized as energy-storing materials due to its large theoretical energy density; as nanoelectronic devices; electrochromic layers, and cathode’s surface of accumulators with large capacity.
The main aim of this study is to synthesize vanadate layers with excellent electrical properties (e.g. large electrochemical capacity, good electrical conductivity). During the synthesis the starting materials (e.g. V2O5, Na, NH4 metavanadate, vanadyl isopropoxide) and synthesis methods are varied. According to pre-experiments and studies, the electrical properties of vanadate systems can be most effectively regulated by the vanadium’ charge of structural units. Thus, the one of the most important tasks in the structure investigation is to determine the chemical bond system and charge of vanadium-containing structural units. For this investigation 51V NMR spectroscopy is best suited and infrared spectroscopy may complete this assay. The effect of cations of vanadate compounds (e.g. H+, NH4+, Na+) or the organic ligands are also aimed to study on the structure and macroscopic properties. The other method to affect the electrical properties may be the intercalation of various ions (e.g. Li ions) between vanadate layers.
Katalin Sinkó, János Rohonczy, Mohammed Bouzbib, Shiro Kubuki