Vanadium oxide electrical properties

In the bulk form, vanadium oxides display different oxidation states and V—O coordination spheres and exhibit a broad variety of electronic, magnetic, and structural properties [96, 97], which make these materials attractive for many industrial applications. Prominent examples range from the area of catalysis, where V-oxides are used as components of important industrial catalysts for oxidation reactions [98] and environment pollution control [99], to optoelectronics, for the construction of light-induced electrical switching devices [100] and smart thermo-chromic windows. In view of the importance of vanadium oxides in different technological applications, the fabrication of this material in nanostructured form is a particularly attractive goal. 

The fabrication process of vanadium oxide (VO2) has also been studied using RBS/C. Since optieal and electrical properties of VO2 are dramatically changed at 68°C due to phase transition, VO2 is regarded as one of the candidates for thermally activated electronic or optical switching devices for optieal fibers or sensors. To obtain the desired properties, the development of the fabrication process for very thin films, without crystalline defects on various substrates, is required. Single-crystalline VO2 thin films on (0001) plane of a sapphire substrate have been synthesized by a laser ablation method. The quality of VO2 was examined by X-ray diffraction and RBS/C method. The eleetrieal resistanee and the optical transmittance of the VO2 film were measured under inereasing and deereasing temperatures. At a temperature of 68 °C, an abrupt transition of resistanee from metal to... 

A review is presented of the electrical properties of polymers filled with different types of conducting particles. Following a theoretical description of a general effective media equation, experimental conductivity-volume fraction data for thermoplastic filled with vanadium oxide particles as well as thermosetting polymer composites, were fitted to the equation. The calculated property-related parameters in the equation are discussed. Data are given for PVC, HDPE, LLDPE, LDPE, and epoxy resin. 12 refs. 

ELECTRICAL PROPERTIES OF NANOSTRUCTURED VANADIUM OXIDE THIN FILMS ON SILICON SUBSTRATES... 

Litzelman SJ, Rothschild A, TuUer HL (2005) The electrical properties and stability of SrTi, jFe, jjOj 5 thin films for automotive oxygen sensor applications. Sens Actuators B 108 231-237 Liu P, Lee S-H, Tracy CE, Turner JA, Pitts JR, Deb SK (2003) Electrochromic and chemochromic performance of mesoporous thin-film vanadium oxide. Solid State Ionics 165 223-228 Liu RQ, Xie YH, Wang JD, Li ZJ, Wang BH (2006) Synthesis of ammonia at atmospheric pressure with Ce M Oj-delta (M=La, Y, Gd, Sm) and their proton conduction at intermediate temperature. Solid State Ionics 177 73-76 Logothetis EM (1980) Resistive-type exhaust gas sensors. Ceram Eng Sd Proc 2 281-301... 

Vanado-phosphate glasses (VPGs) are well known for their semi-conductive behaviour [72]. In the last decades they were widely studied in order to understand the mechanism underneath their electronic properties. The electronic conductivity was correlated to small polaron hopping between vanadium ions with different valence state [86], favoured by their electronic configuration [87]. In VPGs, vanadium atoms are mainly characterized by two oxidation states, 4+ and 5+, and the and based interconnected polyhedra become the preferential path for the polaron hopping [88]. Therefore, the relative amount of these two species (V" + and V +), which is usually expressed as V" +A tot ratio, influences the final electrical properties of VP systems [86, 89]. 

Wu, C. Z., Wei, H., Ning, B., Xie, Y. (2010). New vanadium oxide nanostructures Controlled synthesis and their smart electrical switching properties. Advanced Materials, 22, 1972-1976. 

In situations where the performance is dependent on the uniqueness of the crystal structure of the material, such as the metal-Insulator transition in vanadium oxide, acousto-optic and acoustic-electric responses of AIN, ZnO, PZT, BaTiOg and SrTi03, superconducting properties of copper oxide based perovskites, A-15 silicides, and NbN, wide band gap and dopability of SiC, transistor action in Si/NiSi2(CoSi2)/Sl epitaxial layers etc., it is important to optimize the deposition conditions for the growth of a %[Pg.395]

The structure of MgV Og consists of layers of CO 5 and MgOs pyramids whose bases are coplanar but whose apices alternate in the z direction. A series of oxides and mixed oxides containing have been obtained by hydrogen reduction of alkali-metal vanadates, and the electrical and spectroscopic properties of some vanadium-... 

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