Introductory talk; Conduction in non-crystalline materials

doi:10.1016/0022-3093(72)90112-3

Journal of Non-Crystalline Solids

Volumes 8–10, June 1972, Pages 1-18

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Abstract

The present position of the theory of conduction in non-crystalline materials is reviewed. Particular attention is given to the behaviour at the mobility edge, the Hall effect, hopping at low temperatures, the metal-non-metal transition in a non-crystalline system and to the effect of correlation and of a random concentration of vacancies on the properties of vanadium monoxide.

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Effects of Mn doping on structural properties and conduction mechanism of NaCu<inf>0.2</inf>Fe<inf>0.8−x</inf>Mn<inf>x</inf>O<inf>2</inf> (x = 0.4; 0.5; 0.6; 0.7) materials
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Thickness film effect on charge transport in nanostructure indeno[1, 2-b]fluorene-6,12 dione
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Indeno-fluorene compounds have been applied as organic field-effect transistors. Indeno[1,2-b]flourene-6,12dione (IF-dione) films of different film thickness have been obtained using a thermal evaporating technique. The XRD analysis revealed that the crystalline nature of the IF-dione films with thickness beyond 150 nm had been boosted by increasing the film thickness. The increase of the film thickness from 150 nm to 540 nm led to a rise in the mean crystallite size values from 11.65 to 19.16 nm. The variation of the electrical conductivity of IF-dione thin films with the reciprocal temperatures showed that the thermal activation energy of the sample had been diminished as the film thickness increases. Mott's hopping of variable range conduction operation explained the behavior of the conductivity. The study of the current-density-voltage (J-V) characteristics of IF-dione thin-film confirmed that the Ohmic conduction mechanism is dominant below a threshold voltage (V_t), whereas the space charge limited conduction has been satisfied beyond V_t. It was found that the total trap concentration values are compatible with the other organic molecules. Also, many electrical parameters have been evaluated for different film thicknesses.
Vanadium substituted Li<sup>+</sup>-NASICON systems: Tailoring electronic conductivity for electrode applications
2021, Journal of Alloys and Compounds
Citation Excerpt :
This electronic motion is accompanied by lattice distortion/polarization. Thus, a polaron is the name given to a localized electron whose motion comprises of the motion of the electron and its distorted surroundings [31]. In the V substituted NASICON structured systems, electronic conduction is likely to be governed by polaron hopping.
Mixed ionic-electronic NASICON structured systems namely, LiTi₂(PO₄)_3-x(VO₄)_x and Li_1.3Al_0.3Ti_1.7(PO₄)_3-x(VO₄)_x, for x = 0.1–0.4 have been prepared by partial substitution of V⁵⁺ in place of P⁵⁺ in LiTi₂(PO₄)₃ (LTP) and Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP), respectively. A systematic investigation has been carried out to understand the mechanism of mixed electrical transport by varying the amount of Vanadium in subsequent steps. The structural features of these systems have been studied using XRD and FESEM that suggest Vanadium acceptability in the NASICON type network structure atleast up to x = 0.4 without any notable precipitation. High temperature in situ XRD studies suggest stability of the structure at least up to ∼500 °C. The electronic conductivity in these composites have been attributed to polaron hopping that could be tailored systematically as suggested by dc conductivity studies. The highest total conductivity and electronic conductivity values have been found to be 2 × 10⁻⁴ Ω⁻¹cm⁻¹ and 9 × 10⁻⁵ Ω⁻¹cm⁻¹, respectively for LTP with x = 0.4 at 100 °C. In order to test their potential as electrodes, symmetric cells of the type MIE|LiPF₆/Li₂SO₄|MIE have been fabricated and charged/discharged at different current densities. These materials exhibit appreciable capacity and have been found to be suitable for EDLC/pseudo supercapacitor electrode applications.
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Opening plenary sessionIntroductory talk; Conduction in non-crystalline materials

Abstract

J. Non-Crystalline Solids

J. Non-Crystalline Solids

Solid State Commun.

J. Non-Crystalline Solids

Mater. Res. Bulletin

J. Non-Crystalline Solids

J. Non-Crystalline Solids

J. Non-Crystalline Solids

Phys. Rev.

Ann. Phys. (N.Y.)

J. Phys. C

Phil. Mag.

Phys. Rev.

Progr. Semiconductors

J. Non-Crystalline Solids

Phys. Rev. B

Advan. Phys.

Phil. Mag.

Electronic Processes in Non-Crystalline Materials

Advan. Chem. Phys.

Nachr. Akad. Wiss. Göttingen

J. Phys. C

J. Phys. C

Phys. Today

Opening plenary session
Introductory talk; Conduction in non-crystalline materials