High Electrical Conductivity in Organic Single-Component Systems Based on 2,5-Dimethylthio-TCNQ

1993 ◽  
Vol 328 ◽  
Author(s):  
J. S. Zambounis ◽  
J. Mizuguchi ◽  
H. Hediger ◽  
J. Pfeiffer ◽  
B. Schmidhalter ◽  
...  

ABSTRACT2,5-dimethylthio-TCNQ has been newly synthesized, and its optical and electrical properties have been investigated in evaporated films. A high electrical conductivity of σ=2× 10−5 Scm−l has been measured at room temperature. The present single-component system is found to contain 2×1017 spins/cm3. The charge carriers are presumably due to incorporated impurities which give the ESR signals. Carrier hopping is considerably facilitated by close intermolecular S-N contacts between the S atom of the -SCH3 group of one molecule and the N atom of -C≡N group of the neighboring Molecule.

2019 ◽  
Vol 10 (2) ◽  
pp. 138-150 ◽  
Author(s):  
D. V. Adamchuck ◽  
V. K. Ksenevich

The aim of this work is development of technique for synthesis of tin oxides films with various stoichiometric composition, characterized by high electrical conductivity and light transmittance in the UV and visible range of the electromagnetic spectrum, for their further application as humidity and gas sensors, as well as electrodes for electro-and photocatalytic converters.Nonstoichiometric SnO/SnO2 /SnO2−δ films were synthesized by reactive magnetron sputtering of tin onto glass substrates in argon plasma with oxygen addition and with subsequent thermal oxidation of the formed layers in air. To change the structural, optical, and electrical properties of the films and to find out the optimal synthesis parameters, the oxygen content during the deposition process and the annealing temperature in air were varied in the range of 0–2 vol. % and of 200–450 °C, respectively. The characterization of the films was carried out using a 4-probe method for measuring the electrical resistance, X-ray diffraction, and optical spectroscopy of light transmission.As a result of a comprehensive analysis of the structural, optical and electrical properties of the films, it was found that the optimal synthesis parameters to obtain the most transparent and conductive coatings promising for use as humidity, gas sensors and in photovoltaic devices are the following: oxygen content in argon plasma during sputtering process is ≈ 0,8–1,2 vol. %, the annealing temperature in air is ≈ 350–375 °C. In this case a polycrystalline film with high electrical conductivity and high transmittance in the visible and UV regions of the electromagnetic spectrum with prevailing of tin dioxide phase with structural defects (oxygen vacancies) is formed.


Author(s):  
Вадим Викторович Ефремов ◽  
Михаил Николаевич Палатников ◽  
Ольга Борисовна Щербина

Методом импеданс спектроскопии в области температур 290 - 460 К исследован сегнетоэлектрический твердый раствор LiNaTaNbO со структурой перовскита, синтезированный в условиях высокого давления и температуры. Определены значения статических удельных проводимостей, наиболее вероятные времена релаксации в зависимости от температуры, энтальпии активации носителей заряда и реальная часть диэлектрической проницаемости. Обнаружено, что при комнатной температуре LiNaTaNbO обладает высокой электропроводностью, близкой к суперионной. Обсуждаются возможные механизмы обнаруженных явлений. A ferroelectric solid solution LiNaTaNbO with a perovskite structure, synthesized under the high pressure and temperature conditions, has been studied by impedance spectroscopy in the temperature range 290 - 460 K. The values of static conductivity, the most probable relaxation times as functions of temperature, the activation enthalpy of charge carriers, and the real part of the dielectric constant have been determined. It was found that at room temperature LiNaTaNbO has a high electrical conductivity, close to the superionic one. Possible mechanisms of the discovered phenomenon are discussed.


2018 ◽  
Vol 1 (1) ◽  
pp. 26-31 ◽  
Author(s):  
B Babu ◽  
K Mohanraj ◽  
S Chandrasekar ◽  
N Senthil Kumar ◽  
B Mohanbabu

CdHgTe thin films were grown onto glass substrate via the Chemical bath deposition technique. XRD results indicate that a CdHgTe formed with a cubic polycrystalline structure. The crystallinity of CdHgTe thin films is gradually deteriorate with increasing the gamma irradiation. EDS spectrums confirms the presence of Cd, Hg and Te elements. DC electrical conductivity results depicted the conductivity of CdHgTe increase with increasing a gamma ray dosage


1997 ◽  
Vol 500 ◽  
Author(s):  
M. Park ◽  
G. M. Choi

ABSTRACTComposition. dependence of electrical conductivity of ionic-electronic composite was camined using yttria(8mol%) stabilized zirconia-NiO composites. The contributions of ectronic and ionic charge carriers to the electrical conductivity were determined by Hebb-Vagner polarization technique and electromotive force measurement of galvanic cell. Up to 6 sol% NiO addition, the conductivity decreased since the electronic NiO acted as an insulator in onic matrix. However the ionic transport was dominant until NiO content reaches 26 vol%. Mixed conduction was observed between 26 and 68 vol% of NiO. The effects of composition on he electrical properties were explained by the microstructure and thus by the distribution of two hases.


1997 ◽  
Vol 498 ◽  
Author(s):  
K. F. Chan ◽  
X.-A. Zhao ◽  
C. W. Ong

ABSTRACTCNx films were deposited using pulsed laser deposition (PLD) and ion beam deposition (IBD). The PLD films deposited at substrate temperature Ts = 25°C and high N2 partial pressure have the highest N content (fN) and polymerlike structure, accompanied by large band gap (Eg) and low electrical conductivity (σroom). The rise in Ts lowers fN and induces graphitization of the film structure, so Eg reduces and σroom increases. IBD (with and without N2+ assist) films are graphitic. Higher Ts further enhances the graphitization of the film structure, such that the conduction and valence bands overlap, and σroom approaches to that of graphite. No evidence was found to show successful formation of the hypothetical β-C3N4 phase in the films.


2012 ◽  
Vol 501 ◽  
pp. 319-323
Author(s):  
Hasan A. Alwi ◽  
Lay S. Ewe ◽  
Zahari Ibrahim ◽  
Noor B. Ibrahim ◽  
Roslan Abd-Shukor

We report the room temperature thermal conductivity κ and thermal diffusivity α of polycrystalline La0.7Ca0.3-xSrxMnO3 for x = 0 to 0.1. The samples were prepared by heating at 1220 and 1320oC. The insulator-metal transition temperature, TIM and thermal diffusivity increased with Sr content. Phonon was the dominant contributor to thermal conductivity and the electronic contribution was less than 1%. Enhancement of electrical conductivity σ and thermal diffusivity for x ≥ 0.08 was observed in both series of samples. The grain size of the samples (28 to 46 µm) does not show any affect on the thermal and electrical properties.


Author(s):  
K. L. Levine ◽  
D. V. Ryabokon ◽  
S. D. Khanin ◽  
R. V. Gelamo ◽  
N. A. Nikonorova

The paper studies multilayer graphenes in the form of free-standing films. The authors provide data about the morphology and electrical properties of films treated with plasma of various chemical composition. It is shown that it is possible to control the electrical properties of the surface and electron work function without significantly affecting its morphology. The obtained samples, combining mechanical flexibility with unreactiveness and high electrical conductivity, are promising for application in flexible charge storage devices.


2019 ◽  
Vol 33 (01) ◽  
pp. 1850417 ◽  
Author(s):  
Shuyun Wang ◽  
Kailin Wen ◽  
Yang Sun ◽  
Xianwu Xiu ◽  
Shuyun Teng ◽  
...  

In this paper, NiO/Al/NiO transparent conductive films were prepared by magnetron sputtering at the room temperature. Effects of the NiO and Al layers thicknesses on the optical and electrical properties of the NiO/Al/NiO laminated films were analyzed. When the light wavelength falls in range 300–900 nm, with the increase of the NiO and Al layers thicknesses, the transmittance of the laminated film first increases significantly and then decreases slightly, finally tends to be stable. The laminated film obtained the best optical and electrical properties when the NiO layer is 40 nm and the Al layer is 12 nm. The maximum transmittance is 83%, the average transmittance is 77.3%, the film resistivity is [Formula: see text] and the carrier concentration is [Formula: see text]. At the same time, the transmittance of laminated film is simulated by FDTD software. But the simulation curve is different from the experimental data. Analysis results show that, with the NiO dielectric is added on both sides of the metal Al film, the light reflection characteristic of laminated film has been completely different from that of the single Al metal film because of the change of interface characteristics between Al film and NiO film, and the actual luminous transmittance greatly increases.


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