Vanadium compounds intercalation

Another vanadium oxide that has received much attention is LiVaOs, which has a layer structure composed of octahedral and trigonal bipyramidal ribbons that can be swelled just like other layered compounds and can intercalate lithium. Here again, the method of preparation is important to its electrochemical characteristics. West et al. made a systematic study of the impact of synthesis technique on capacity and cycling and showed that amorphous material increased the capacity above 2 V from 3—4 lithium per mole of LiVsOs at low current drains, 6—200 fiAlcm. ... 

The last option is the most restrictive, while the first alternative is the most relaxed. For example, when V and O are included in the list, then Exclusive AND limits the search only to oxides of vanadium, while compounds containing other elements (e.g. vanadium hydroxides, vanadates, etc.) will not be considered and analyzed, On the other hand, Inclusive AND searches among all compounds containing both V and O in combination with any other chemical elements. The latter option may be useful, for example, when intercalates of vanadium oxides are suspected or studied. 

Oxovanadium phosphate VOPO4.2H2O is used as a catalyst, or catalyst precursor. It is a layered compound in which six oxygen atoms around the vanadium form an almost regular octahedron. The weaker interlayer binding makes VOPO4.H2O and its analogs attractive as potential hosts for coordination—intercalation reactions [5—11]. 

Intercalation reactions of neutral host lattices usually occur via electron transfer between the guest species and the host lattice. Furthermore, vanadium (V) compounds are strong oxidants, and vanadium phosphate catalysts are able to promote, for example, oxidation of alcohols to ketones [12]. 

The synthesis and characterization of VOPO4 intercalation compounds with aliphatic amines from Cj to Cjo have been reported [13,14]. However, the synthetic approach for the intercalation of such classes of molecules in this work is quite different from those used here. Furthermore (and most important), we think that the use of diamines could provide interesting results, from a structural point of view, since they exhibit two coordination sites (N atoms), and so are able to interact (coordinate) with two different vanadium atoms of opposite layers. 

Orthorhombic crystalline vanadium pentoxide is a typical intercalation compound as a result of its layered structure, see Fig. 5.2, which finds widespread use in lithium ion intercalation applications such as electrochromic cells [17], high energy density batteries [18], supercapacitors [19], and sensors [20], since it offers the essential advantages of low cost, abundant availability, easy synthesis, and high intercalation densities [15, 16]. 

The most common intercalation compounds employed by LPBs are vanadium oxide, V60i3(5, 11-14), vanadium bronze, LiVsOs (15-18), titanium disulphide, TiS2[12], titanium dioxide, Ti02[19] and lithium-manganese-oxide spinel Lii+xMn2O4[20]. The amount of lithium which can be reversibly intercalated in the various cited compounds, namely the value of X in equation [6.2], varies from case to case. Accordingly, the value... 

Electrochemical Lithium Intercalation Reaction of Anodic Vanadium Oxide Film. J. Alloys Compounds 217, 52—58. 

Gavrilyuk VI, Plakhotnik VN (1994) Thermodynamics of Compounds of Lithium Intercalation into Vanadium Pentoxide. Russ J Phys Chem 68 1373-1376... 

Lithium-metal-polymer (LMP) is a relatively new technology being promoted by the Canadian Avestor Limited Partnership based in Boucherville, Quebec, for telecommunications applications. Avestor s LMP cell is built up from four elements. An ultra-thin metallic lithium foil anode combines the roles of lithium source and current collector. The solid polymeric electrolyte is made by dissolving a lithium salt in an appropriate co-polymer. The metallic oxide cathode is based on a reversible intercalation compound of vanadium oxide, blended with a lithium salt and a polymer to produce a plastic composite. Finally, an aluminium foil forms the current collector. Avestor cells can operate within the temperature range -40 °C to +65 °C. 

This cell type, marketed by Matsushita, operates with heavy metal oxide intercalation compounds on both the anodic (niobium oxide) and cathodic (vanadium oxide) side. The system is especially capable of rapid recharge. Deep discharge is tolerated well. With shallow discharges one may expect more than 700 cycles. The button cell size 1616 shows an energy density of 37Wh/L. 

Murphy DW (1982) Lithium intercalation compounds of vanadium chalcogenides. In Whittingham MS, Jacobstm AJ (eds) Intercalation chemistry. Academic, New York, pp 563-572... 

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