Research On Preparation, Characterization And Application Of Polyvanadate As The Matrix

The sensitivity and selectivity of V2O5 thin films used as gas-sensing materials can be improved by doping. The gas sensors of V2O5, Pd-V2O5 and Ag-V2O5 have been prepared by blending method. The effect Pd, Ag on sensitivity, selectivity and response-recovery behavior of gas sensor were investigated. The best doping content were determined. The gas sensing mechanism was analyzed using the model of surface space-charge layer and interface barrier for grains.Poly-vanadium-molybdenum acid xerogel thin films have been fabricated using V2O5, Mo powders and H2O2 as the precursors. The obtained xerogels were investigated by XPS, TGA, XRD and IR. The effect of frequency, the content of molybdenum, the thickness of thin films, electrode materials and temperature on the humidity sensing properties of the prepared thin films were discussed and the humidity mechanism was analyzed.Poly-vanadium-titanium acid xerogel thin films have been fabricated using V2O5 powders and titanium tetrabutylate as precursors. The obtained xerogels were investigated by IR, XPS, TGA and XRD methods. The humidity sensitive properties, the response -recovery behavior and long-term stability of the thin films were studied.The humidity sensing properties of poly-vanadium-molybdenum acid xerogel thin films are good, but its long-term stability need to improve. Polyaniline can be inserted in poly-vanadium-molybdenum acid xerogel to produce organic-inorganic nanocomposites which can improve long-term stability of poly-vanadium-molybdenum acid xerogel because of the excellent water resistance of polyaniline. The structure and properties of poly-vanadium-molybdenum acid xerogel as promising functional materials change with the content of molybdenum. PAn/poly-vanadium-molybdenum acid nanocomposites are fabricated by sol-gel method and in situ oxidative polymerization. The properties of nanocomposites were characterized by XRD, IR, SEM and complex impedance measurement. The effect of the content of aniline on the humidity sensing properties of nanocomposites was discussed.The electrochemical properties of PAn/V2O5 need to improve as electrode materials. The poly-vanadium-molybdenum acid xerogel can be used as intercalation complex due to its layer-structure. Polyaniline/poly-vanadium-molybdenum acid namocomposites were fabricated by blending method. The nanocomposites were characterized by XRD and IR combined with electrochemical tests. Results show that the electrochemical properties and cycle stability are enhanced due to the introduction of polyaniline. (PAPSA)1H2V10Mo2O32·nH2O exhibits an initial discharge capacity of 275mAh/g and the discharge capacity is 214mAh/g, the capacity retention rate was 78% after 80 cycles.