Conjugation effects on carrier mobilities of polythiophenes probed by time-resolved terahertz spectroscopy

Esentürk, Okan
Deongchamp, Dean M.
Heilweil, Edwin J.
Optically generated carrier conductivity of thiophene-based spin-cast polymer films, as cast poly(3-hexylthiophene) (P3HT) and both as cast and above liquid crystalline temperature annealed poly(2,5-bis(3tetradecylthiophen-2yl)thieno[3,2-b]thiophene) (PBTTT), were measured by time-resolved THz spectroscopy (TRTS) and compared to reported thin-film transistor (TFT) device measurements. The relative mobilities of the samples measured by TRTS agree well with reported TFl` mobilities. Since TRTS is sensitive to shortrange carrier mobility, this study suggests that increased mobility of PBTTT relative to P3HT films arises from improved ordering of the local structure, increased effective conjugation length, and planarity of PBTTT molecules in the solid state.


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Details of coupling a catalytic reaction chamber to a liquid nitrogen-cooled cryofocuser/triple quadrupole mass spectrometer for online monitoring of nitric oxide (NO) photocatalytic reaction products are presented. Cryogenic trapping of catalytic reaction products, via cryofocusing prior to mass spectrometry analysis, allows unambiguous characterization of nitrous oxide (N2O) and nitrogen oxide species (i.e., NO and nitrogen dioxide (NO2)) at low concentrations. Results are presented, indicating that the m...
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The adsorption of perylenediimide (PDI)-based dye compounds (BrPDI, BrGly, and BrAsp) on the defect-free unreconstructed (UR) rutile TiO2(110) surface has been studied using total energy pseudopotential calculations based on density functional theory. All dye molecules form moderate chemical bonds with the defect-free UR rutile (110) surface in the most stable adsorption configurations. Electronic structure analysis reveals that HOMO and LUMO levels of the adsorbed dye molecules appear within the band gap a...
The effect of substrate and post-annealing temperature on the structural and optical properties of polycrystalline InSe thin films
Parlak, Mehmet (Elsevier BV, 1998-06-08)
X-ray diffraction, scanning electron microscopy, compositional analysis and transmission measurements are performed on InSe thin films grown by thermal evaporation at different substrate and annealing temperatures of 150-250 degrees C and 100-200 degrees C, respectively. An analysis of structural measurements indicates that there exist three phases of In-Se system like InSe, In2Se3 and In6Se7 in the same film at low-substrate temperature, but at high-substrate temperatures, In2Se3 phase was absent. The comp...
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Metal-Enhanced Fluorescence from Silver Nanowires with High Aspect Ratio on Glass Slides for Biosensing Applications
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High enhancement of fluorescence emission, improved fluorophore photostability, and significant reduction of fluorescence lifetimes have been obtained from high aspect ratio (>100) silver (Ag) nanowires. These quantities are found to depend on the surface loading of Ag nanowires on glass slides, where the enhancement of fluorescence emission increases with the density of nanowires. The surface loading dependence was attributed to the creation of intense electric fields around the network of Ag nanowires and...
Citation Formats
O. Esentürk, D. M. Deongchamp, and E. J. Heilweil, “Conjugation effects on carrier mobilities of polythiophenes probed by time-resolved terahertz spectroscopy,” JOURNAL OF PHYSICAL CHEMISTRY C, pp. 10587–10590, 2008, Accessed: 00, 2020. [Online]. Available: