New concept and electrochemistry of in situ non-covalent immobilization of redox molecules for energy storage applications

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Interest of Redox Molecular Grafting for Energy Storage Applications

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The contribution of the dielectric spectroscopy to the multiscale study of the electrode materials

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Dielectric study of v2O5-1.6 H2O xerogel in the broad frequency range (10^5-10^10 hz)

The first experimental results concerning the dielectric properties of V2O5-1.6 H2O xerogel in a broad frequency range (105-1010 Hz) are presented between the temperatures 198 K and 296 K. The dielectric spectra exhibit four behaviour types : a) a low frequency effect due to the diffusion of charge carriers H+ protons ; b) two dielectric relaxations due to the two kinds of water : water strongly-bonded and water weakly-bonded to the V2O5 ribbon; c) a dielectric relaxation which would be due to a fast rotation of the H3O+ ions. One explanation of these mechanisms with respect to the experimental results is proposed.Les premiers résultats expérimentaux concernant les propriétés diélectriques dans une large bande de fréquences (105-1010 Hz) du xérogel d'oxyde de vanadium (V2O5-1,6 H2O) sont présentés entre 198 K et 296 K. Les spectres diélectriques montrent quatre types de comportements : a) un effet de basse fréquence dû à la diffusion des porteurs de charges (protons H+); b) deux relaxations diélectriques dues aux deux sortes d'eau : une eau fortement liée et une eau faiblement liée au feuillet de V2O 5 ; c) une relaxation diélectrique qui serait due à une rotation rapide des ions H3O+. Une compréhension de ces mécanismes en fonction des résultats expérimentaux est proposée

Phase transitions and dielectric relaxations in superionic protonic conductor HUP (H3OUO2PO4.3H2O) in the broad frequency range (10-2-1010 Hz)

The dielectric properties of hydrogen uranyle phosphate (HUP = H3 OUO2PO4.3H2O) and its sodium homologous (NaUP = NaUO2PO4, 3 H2O) have been studied between 10-2 and 1010 Hz. The samples are dense polycrystalline pellets sintered under pressure at 25°C. Three or two dipolar relaxations are observed for HUP or NaUP respectively and assigned to protonic species reorientations (H2O, H3O+), to H3O + ions or to ions coupled water molecules jumps. Dipolar relaxation, ferroelectricity and superionic conductivity are discussed.Les propriétés diélectriques du phosphate d'uranyle hydraté d'oxonium (HUP = H3OUO2PO4.3H2O) et de son dérivé (NaUP = NaUO2PO4.3 H2O) sous forme d'échantillons denses, polycristallins, préparés par frittage sous charge à 25°C ont été étudiées entre 10-2 et 1010 Hz. Trois ou deux relaxations dipolaires différentes ont été observées pour HUP ou NaUP respectivement et attribuées aux processus de réorientation des espèces protoniques (H 2O, H3O+), aux sauts des ions H3O + ou aux molécules d'eau couplées aux ions conducteurs. Les relations entre relaxation dipolaire, ferroélectricité et superconduction ionique sont discutées

Infrared electroactive materials and devices

Light and flexible optical batteries based on plastic lithium-ion battery (PliON) technology have been recently proposed, and are able to modulate their reflection in the infrared range. We have focused our interest in the wavelength range 3-5 and 8-12 μm range corresponding to two optical windows of light propagation in the atmosphere. The original feature of this device is that it uses material powder embedded in a plastic matrix. The choice of materials to obtain significant contrasts is discussed. According to the type of materials (metal or semiconductor), the influence of their nature, their morphology and their structures on the optical properties is underlined. The optical behaviors of low or high absorptive compounds have been understood and correlated to the particle size. The main important point is that high reflection can be obtained with high absorptive or transparent particles unlike the thin layer device. Some parameters are investigated in order to improve to final device. © 2006 Elsevier Ltd. All rights reserved

Radio and microwave frequency relaxations and conductivity in superionic Nasicon

8th solid state ionics conference, Lake Louise (Canada), October 20-26, 1991. Journal of solid state ionicsSIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : 22419, issue : a.1991 n.207 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Quality control tools of electrode coating for Li-ion batteries

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