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

Abstract

2014 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 V2O5 ; 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.

Vanadium Oxide Gel Films: Optical and Electrical Properties, Internal Electrochromism and Effect of Doping

“…The Cole-Cole diagram (Fig. 4, b) is similar to that for V2O5×1.8H2O presented in [3], [32]. A straight line at low frequencies corresponds to the diffusion of charge carriers.…”

Proton and electron conduction in polymer intercalated vanadium pentoxide xerogel

“…Ice reveals dielectric loss peak in kHz region. Debye like behavior is found for water and ice with relaxation activation energy 220 and 580 meV, respectively [31]. The observed non-Debye peaks within MHz frequency region and relatively lower activation energy are not due to water and ice.…”

High-Density Near-Field Readout over 50 GB Capacity Using Solid Immersion Lens with High Refractive Index

“…The experimental device, which has been fully described in previous papers [21,[35][36][37][38][39], consists of a coaxial cell (APC7 standard) in which the cylindrically shaped sample fills the gap between the inner conductor and a short-circuit (figure 2(a)). The sample and the inner conductor axis (z-axis) are identical.…”

“…As the possible dielectric relaxations are not clearly shown in frequency-dependent representations, it is more suitable to use Cole-Cole (CC) plots in order to get an easier decomposition of the dielectric spectra. To provide evidence for the dielectric relaxations, we employed a procedure of decomposition of the CC plots, which has been fully described elsewhere [21,[37][38][39]. Figure 4(a) shows the entire CC plot (from 10 to 10 10 Hz) of LNOA at room temperature.…”

“…If we consider a double-well system between two finite potential barriers, the model of Odagaki et al [24] predicts one Debye dielectric relaxation. According to Fröhlich [25] and Bosman and van Daal [17], the Debye dielectric relaxation can only occur with small-polaron formation in low-mobility semiconductors [26][27][28][29][30][31][32][33][34][35][36][37][38]. As the dielectric relaxation is the result of an electric dipole reorientation, we have to consider only local (confined) hopping of small polarons around an immobile ion [17,21,29] or in a double-well system between two finite potential barriers [24,30].…”