Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 17

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

Search:
in the keywords:  73.61.Ph
help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Simple Model for Elucidation the Nature of Current-Generating Processes in Polyaniline-Type Conductive Polymers

100%
Barsukov V., Chivikov S.
Acta Physica Polonica A
|
1995
|
vol. 87
|
issue 4-5
905-908
EN
According to suggested simple model in the practically important po­tential range (E ≈ 0... + 0.6 V against SHE) the nature of the electro­chemical current-generating processes in conductive polymers of polyaniline type is not associated with a particular redox reaction, but it reduces to the charge/discharge of the double electric layer capacity, which is anomalously high (300... 850 F/g) in such systems due to structural peculiarities of these materials. The model gives a good fit to electrode behavior in this range.
2
Content available remote

Electrical Characterization of Semiconducting Polymers

63%
Stallinga P., Gomes H., Jones G., Taylor D.
Acta Physica Polonica A
|
1998
|
vol. 94
|
issue 3
545-548
EN
Schottky diodes resulting from an intimate contact of aluminum on electrodeposited poly(3-methylthiopene) were studied by admittance spectroscopy, capacitance-voltage measurements and voltaic and optically-induced current and capacitance transients. The loss tangents show the existence of interface states that can be removed by vacuum annealing. Furthermore, the C-V curves contradict the idea of movement of the dopant ions.
3
Content available remote

D.C. Conductivity of Polymer Composites with (BEDT-TTF)_{2}I_{3} Superconductor

63%
Ulański J., Jeszka J., Polanowski P., Głowacki I., Kryszewski M., Staerk D., Helberg H.
Acta Physica Polonica A
|
1995
|
vol. 87
|
issue 4-5
899-903
EN
Electrical properties of conducting reticulate doped polymeric films con­taining BEDT-TTF iodide crystalline network were investigated. Conditions of preparation of this kind of films i.e. time of doping by iodine vapours and time and temperature of annealing and their influence on transformation of the BEDT-TTF iodide crystallites into superconducting phase are discussed.
4
Content available remote

Charge Carrier Transport in Non-Homogeneous MDMO-PPV Polymer

51%
Kažukauskas V., Pranaitis M., Janonis V.
Acta Physica Polonica A
|
2011
|
vol. 119
|
issue 2
128-130
EN
By thermally stimulated currents we have investigated carrier transport and trapping in [poly-(2-methoxyl, 5-(3,77dimethyloctyloxy)] paraphenylenevinylene (MDMO-PPV). To assure selective excitation of the defect states the spectral width of the exciting light was varied from 1.77 eV up to 3.1 eV. The thermally stimulated current curves were shown to be a superposition of carrier generation from trapping states and thermally stimulated mobility growth. The extrinsic excitation resulted in 0.16 eV photoconductivity effective activation energy values, which decreased down to 0.05 eV for the intrinsic excitation. The deeper states with activation energies of 0.28-0.3 eV and 0.8-0.85 eV were identified, too. The results are direct indication of distributed in energy trapping and transport states with the standard deviation of the density of states of about 0.015 eV.
5
Publication available in full text mode
Content available

Trapping of Charge Carriers in Organic Molecular Materials: Phthalocyanine Thin Films Revisited

51%
Zhivkov I., Nešpurek S., Sworakowski J.
Acta Physica Polonica A
|
2001
|
vol. 100
|
issue Supplement
215-228
EN
The technique of temperature-modulated space-charge-limited currents was employed to study the energetic distribution of local states in thin films of metal-free phthalocyanine. Four well-defined local levels were detected within the energy range 0.5-0.3 eV, accompanied by an onset to a manifold of shallower states. The morphology of the films, depending on the deposition rate and changing from polycrystalline to nearly amorphous, affects the densities of local states but not their energies.
6
Content available remote

Optical, Structural, and Electrical Properties of Aromatic Triphenylamine-Based Poly(azomethine)s in Thin Layers

51%
Palewicz M., Iwan A., Sikora A., Doskocz J., Strek W., Sek D., Mazurek B.
Acta Physica Polonica A
|
2012
|
vol. 121
|
issue 2
439-444
EN
Spectroscopic and photophysical properties of the poly(azomethine)s with triphenylamine moieties were investigated by UV-vis, X-ray diffraction and atomic force microscopy methods. Current-voltage measurements were performed on ITO/polymer/Alq_3/Al, ITO/PEDOT/polymer:MWCNT/Al and ITO/polymer:MWCNT/Al devices. Multiwall carbon nanotubes were blended with polymer in the ratio 1:1. The lowest optical band gap value at 2.33 eV was detected. Moreover, an absorption coefficient α was calculated from transmission and reflectivity measurements. In this paper, we presented photophysical and structural properties of the poly(azomethine)s in solid state of great interest for the emerging field of molecular electronics and for their uses as active layers in (opto)electronic devices such as solar cells.
7
Content available remote

Effect of Molecular Orientation on Photovoltaic Efficiency and Carrier Transport in a New Semiconducting Polymer

51%
Kažukauskas V., Pranaitis M., Sentein C., Rocha L., Raimond P., Duyssens I., Van Severen I., Lutsen L., Cleij T., Vanderzande D.
Acta Physica Polonica A
|
2008
|
vol. 113
|
issue 3
1009-1012
EN
New functionalized soluble poly(p-phenylene vinylene) derivative bearing polar molecules was designed and synthesized in order to investigate effects of molecular orientation in polymer photovoltaic devices. The active polar molecule is the 4-(N-butyl-N-2-hydroxyethyl)-1- nitro-benzene group. The grafting of the push-pull molecule with a donor/transmitter/acceptor structure, possessing a large ground state dipole moment, enables the molecular orientation by a dc electric field. An internal electric field stored in such system facilitates exciton dissociation and improves charge transport in single-layer devices. In our systems an increase in the external quantum efficiency by a factor of about 1.5 to 2 is estimated. The associated effects of orientation on the carrier injection and transport properties were evidenced.
8
Content available remote

Transport and Relaxation of Charge in Organic-Inorganic Nanocomposites

51%
Olenych I., Aksimentyeva O., Tsizh B., Horbenko Y.
Acta Physica Polonica A
|
2018
|
vol. 133
|
issue 4
851-855
EN
In this work the nanocomposites of poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate) host matrix with porous silicon and ZnO nanoparticles were manufactured. The charge transport and relaxation processes in organic-inorganic nanocomposites were analyzed based on complex studies of electrical conductivity and depolarization current in the wide temperature range. By means of impedance spectroscopy we have established that increase of content of ZnO nanoparticles causes the rise in the internal resistance of the hybrid films. Based on the spectra of thermally stimulated depolarization current the localized electron states in the experimental samples are found. The combination of the porous silicon and zinc oxide nanoparticles provides an increase of surface area of the sensors and their high sensitivity to water molecules.
9
Publication available in full text mode
Content available

Third Harmonic Generation Susceptibility of Polyacetylene in Terms of the Chain Temperature

51%
Sabra M.
Acta Physica Polonica A
|
2006
|
vol. 109
|
issue 6
761-774
EN
The tight binding Hamiltonian of Su, Schrieffer, and Heeger has been used to describe the physical properties of the polyacetylene chain. The chain temperature is calculated from the potential energy which is directly related to the CH group displacement. Two different forms of the displacements have been considered: random and Gaussian. The third harmonic generation susceptibility spectra have been plotted in terms of the temperature using the four-wave mixing formula. The results show that a second peak at the mid gap energy has occurred for room temperature which is in good agreement with the experimental data.
10
Content available remote

Polymers with π-Electrons Delocalised along Pendant Group Stacks

51%
Ulański J., Κryszewski M.
Acta Physica Polonica A
|
1995
|
vol. 88
|
issue 3
543-547
EN
Recently developed photoconductive polymer systems, polyparacyclophanes doped with low-molecular-weight acceptors, combine high charge carrier mobility provided by extended π-electron systems along cofacially arrayed aromatic rings, with effective photogeneration in visible range due to formation of charge-transfer complexes with the dopants. In a series of polyparacyclophane complexed with different benzoquinones it was found that the photoconductivity gain coefficient in the visible range increases with increasing electron affinity of the dopant and that the gain coefficient is higher for higher dopant concentration. The influence of the charge-transfer complex formation between various polyparacyclophanes and various acceptors on the charge carrier generation both in the dark and under illumination is discussed.
11
Content available remote

Rectification in Fullerene (C_{60})-Phthalocyanine Thin Film Sandwich Structures

51%
Anderson T., Akselrod L., Fischer C. M., Roth S.
Acta Physica Polonica A
|
1995
|
vol. 87
|
issue 4-5
877-880
EN
Bilayer sandwich structures were fabricated by the sequential thermal evaporation of gold, copper phthalocyanine (CuPc), C_{60} and gold onto sap­phire substrates. When the current-voltage characteristics of a freshly made device are measured in an atmosphere of argon, fairly strong rectification is observed. When the bilayer device is exposed to ammonia vapor, the recti­fication slowly decreases and almost disappears. If the device is then placed under vacuum and the ammonia removed, the initial conditions slowly re­turn. We attribute the rectification to the formation of a p-n junction.
12
Content available remote

The Influence of PEDOT to PSS Ratio on the Optical Properties of PEDOT:PSS Thin Solid Films - Insight from Spectroscopic Ellipsometry

51%
Bednarski H., Hajduk B., Jurusik J., Jarząbek B., Domański M., Łaba K., Wanic A., Łapkowski M.
|
EN
In this work, we study the influence of the PEDOT to PSS ratio on the optical properties of PEDOT:PSS thin solid films using spectroscopic ellipsometry and UV-vis spectrometry. In the data analysis, we develop a consisted composition dependent optical model of PEDOT:PSS. This enabled us to account for contributions from PSS part within the Tauc-Lorentz optical model and from PEDOT part within the Drude-Lorentz optical model. Moreover, we relate the optical properties of PEDOT:PSS thin solid films to their electrical specific conductivities in the frame of the generalized effective medium theory. Determined in this manner electrical conductivities of five commercially available water dispersions of PEDOT:PSS are compared with their nominal values.
13
Content available remote

Photoelectron Emission Microscopy and its Application to the Study of Polymer Surfaces

51%
Cossy-Favre A., Diaz J., Anders S., Padmore H., Liu Y., Samant M., Stöhr J., Brown H., Russell T. P.
|
EN
The X-ray photoelectron emission microscopy at the Advanced Light Source has a spatial resolution of 0.2 microns at an accelerating voltage of 12 kV. The tunability of the photon energy is used to provide chemical state information using near edge X-ray absorption fine structure spectroscopy on the sub-micrometer scale. The homogeneity of thin films of polymer blends was studied for various film thicknesses. The polystyrene/polyvinylmethylether film of 194 Å showed protrusions of 2-3 μm diameter with an enriched polystyrene content while the polystyrene/polystyreneacrylonitrile 504 Å thick films showed 5-6 μm segregated regions without any topological structure.
14
Content available remote

Fabrication and Study of the Organic-Inorganic Semiconductor Diodes Formed on n-Si

51%
Vengalis B., Šliužienė K., Lisauskas V., Grigaliūnaitė-Vonsevičienė G., Butkutė R., Lygaitis R., Gražulevičius J.
Acta Physica Polonica A
|
2011
|
vol. 119
|
issue 2
262-264
EN
We report fabrication and electrical characterization of the organic-inorganic semiconductor diode structures formed by evaporating thin films of three novel low molecular mass organic compounds on n-type Si substrates. The organic compounds containing carbazole and triphenylamine structural units, namely: 9,9'-bis(4-butylphenyl)-3,3'-bicarbazolyl (BPBC), 4-(1H-perimidin-2-yl)-N,N-diphenylbenzenamine (PER) and 9,9'-diethyl-3,3'-bicarbazolyl (EBC) have been synthesized. The current-voltage characteristics of the Au/(BPBC, EBC, PER)/n-Si diode structures measured at T = 295 K revealed rectifying behavior with a potential barrier height values of 0.71 eV, 0.73 eV, 0.76 eV, respectively.
15
Content available remote

Investigation of Local Trapping States in Organic Molecular Crystals by Method of Thermally Modulated Space-Charge Limited Current

45%
Muzikante I., Silinsh Ε. A.
Acta Physica Polonica A
|
1995
|
vol. 88
|
issue 2
389-399
EN
The method of thermally modulated space-charge limited current has been used for studying local charge carrier trapping state energy spectra in vacuum evaporated thin films and Langmuir-Blodgett multilayers of different organic molecular crystals. In case of evaporated thin polycrystalline layers of pentacene four sets of local trapping states in energy range from E_{t} = 0.35 to 0.06 eV were observed. In evaporated thin layers of dimethylaminobenzylidene indandione-1,3 five sets of trapping states from Ε_{t} = 0.59 to 0.28 eV were detected. In the evaporated layers of indandione-1,3 pyridinium betaine only a single set of very shallow trapping states close to the conductivity level was observed. In the Langmuir-Blodgett multilayers of vanadyl phthalocyanine and indandione-1,3 pyridinium betaine the activation energy E_{a} dependence on applied voltage U, E_{a}(U), for bulk conductivity is not step-like as in case of evaporated layers, but of rather complicated, oscillatory shape. Such character of the E_{a}(U) dependence may be explained by the specific quantum well structure of the Langmuir-Biodgett multilayers and spatially nonuniform trap distribution. However, for in-plane conductivity of indandione-1,3 pyridinium betaine films the E_{a}(U) dependence is step-like and two sets of trapping states at E_{t} = 0.45 ± 0.03 eV and E_{t} = 0.18 ± 0.03 eV were obtained. In case of bulk conductivity of the Langmuir-Blodgett layers the activation energy E_{a} at sufficiently high electric fields drops down to zero and the charge carrier transport switches to a "trap-free" regime.
16
Content available remote

Electrical properties and memory effect in the field effect transistor based on organic ferroelectric insulator and pentacene

38%
Matsuo Y., Ijichi T., Yamada H., Hatori J., Ikehata S.
Open Physics
|
2004
|
vol. 2
|
issue 2
357-366
EN
We have fabricated a field effect transistor (FET) based on an organic ferroelectric insulator and molecular conductor, and investigated the electrical properties and memory effects on the PEN-FET. We have observed a drastic change in the drain current at around the coercive electric fieldE c of the organic ferroelectric insulator in not only a FET (PEN-FET) based on a pentacene (PEN) film but also a FET (IPEN-FET) based on an iodine doped PEN film. The magnitude of the change of the drain current for the IPEN-FET is 200 times larger than that for the PEN-FET. It is expected from these results that the PEN-FET (especially the IPEN-FET) is an improvement in such devices, since it operates at a low gate electric field accompanied by the appearance of the spontaneous polarization in the organic ferroelectric insulator. In addition, we have found that the drain current for the PEN-FET does not return to the initial drain current ofE G=0 V/cm for more than one week, even if the gate electric field is changed to 0 V/cm from 500 V/cm(>E c). From these results, it is suggested that the PEN-FET becomes a memory device.
17
Content available remote

Mott-Schottky Analysis of the P3HT:ZnS_{cubic} and P3HT:ZnS_{hexa} Bulk Heterojunction Solar Cells

32%
Abdul Kareem T.
Acta Physica Polonica A
|
2016
|
vol. 129
|
issue 3
409-413
EN
Bulk heterojunction solar cells of sphalerite and wurtzite ZnS incorporated P3HT were fabricated and their Mott-Schottky analysis was performed to find the conduction mechanism of the devices. The analysis shows the formation of a Schottky junction and band unpinning at the P3HT:ZnS-Al contact and it confirms the hole conductivity in the active material.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.