Electrical transport, optical and thermal properties of polyaniline-pumice composites

Akgoz, A.
Cabuk, M.
Karaagac, H.
YAVUZ, Mustafa
In this study, electrical conductivity, photoconductivity, absorbance and thermal properties of polyaniline (PANI) and polyaniline-pumice composites were investigated. Temperature dependent conductivity and photoconductivity measurements were carried out in the temperature range of 80-400K. The measurements revealed that the dominant conduction mechanisms in polyaniline and 15% pumice doped composite were hopping conduction. The low activation energies calculated for 36% pumice doped composite indicated that this sample has highly defective and degenerate structure due to the high pumice content. Polyaniline and pumice doped composites showed semiconductor behavior with the exponential variation of inverse temperature dependence of electrical conductivity. Photoconductivities of the PANI and PANI-pumice composites under various illumination intensities were studied and it was found for all samples that the conductivity increased with increasing temperature and light intensity, but decreased with increasing pumice content in the structure. Absorbance spectrum has been determined in the wavelength range of 300-700 nm and it was found that the band gap values decreased as the pumice content was increased. Thermogravimetric analysis have shown for all samples that the mass loss has started above around 300 K due to the loss of moisture from the structures. As a result of this work, it was found that polyaniline and polyaniline-pumice composites had low resistivity and high band gaps and could be used as a window layer semiconductor in heterojunction solar cell applications.


Optical properties of Cu3In5S9 single crystals by spectroscopic ellipsometry
Işık, Mehmet; Nasser, H.; Ahmedova, F.; Guseinov, A.; Hasanlı, Nızamı (2018-01-01)
Cu3In5S9 single crystals were investigated by structural methods of x-ray diffraction and energy dispersive spectroscopy and optical techniques of ellipsometry and reflection carried out at room temperature. The spectral dependencies of optical constants; dielectric function, refractive index and extinction coefficient, were plotted in the range of 1.2-6.2 eV from ellipsometric data. The spectra of optical constants obtained from ellipsometry analyses and reflectance spectra presented a sharp change around ...
Optical characterization of Ga2SeS layered crystals by transmission, reflection and ellipsometry
IŞIK, MEHMET; Hasanlı, Nızamı (2015-07-10)
Optical properties of Ga2SeS crystals grown by Bridgman method were investigated by transmission, reflection and ellipsometry measurements. Analysis of the transmission and reflection measurements performed in the wavelength range of 400-1100 nm at room temperature indicated the presence of indirect and direct transitions with 2.28 eV and 2.38 eV band gap energies. Ellipsometry measurements were carried out in the 1.2-6.0 eV spectral region to get information about optical constants, real and imaginary part...
Absorption edge and optical constants of Tl2Ga2S3Se crystals from reflection and transmission, and ellipsometric measurements
Isik, M.; Hasanlı, Nızamı (2012-06-15)
The optical properties of Tl2Ga2S3Se layered crystalline semiconductors were investigated from transmission, reflection and ellipsometric measurements. The experimental results of the room temperature transmission and reflection measurements performed in the wavelength range of 400-1100 nm showed the presence of both indirect and direct transitions in the band structure of the crystals with 2.38 and 2.62 eV band gap energies.
Thermal degradation of polythiophene-natural rubber and polythiophene-synthetic rubber conducting polymer composites
Hacaloğlu, Jale; Akbulut, Ural; Toppare, Levent Kamil (1997-01-01)
Thermal degradation of conducting polymer composites of polythiophene and rubbers was studied by direct and indirect pyrolysis mass spectrometry techniques. The samples were prepared by electrooxidation of polythiophene using natural rubber or synthetic rubber as the insulating matrix. Presence of decomposition products which were not observed during pyrolysis of pure polythiophene and rubbers, and disappearance of rubber-based pyrolysis mass peaks, together with changes in thermal stability and behaviour, ...
Comparative study on mechanical, thermal, viscoelastic and rheological properties of vulcanised EPDM rubber
Çavdar, Şeyma; Ozdemir, T.; Usanmaz, Ali (Informa UK Limited, 2010-07-01)
In this study, mechanical, thermal and rheological properties of vulcanised ethylene propylene diene monomer (EPDM) rubber containing different amounts of vulcanising agent, filler, paraffinic oil and stearic acid were compared. Moreover, reaction rate constant of the curing reaction has been calculated from the results of the rheological tests, and relative change of rate constant with the change of additives was studied by a new method. Thermal gravimetric analysis with in situ Fourier transform infrared ...
Citation Formats
K. YILMAZ, A. Akgoz, M. Cabuk, H. Karaagac, O. KARABULUT, and M. YAVUZ, “Electrical transport, optical and thermal properties of polyaniline-pumice composites,” MATERIALS CHEMISTRY AND PHYSICS, pp. 956–961, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/68329.