Browse
Submit Data
Databases
API
Help

Dataset Information

5 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

An effect of molecular motion on carrier formation in a poly(3-hexylthiophene) film.

ABSTRACT: Free carriers, polarons (P), in conjugated polymers play a key role in the performance of optoelectronic devices. Here, we present solid evidence that P can be predominantly generated from polaron pairs (PP) in a poly(3-hexylthiophene) (P3HT) film under zero electric field. P formation from PP strongly depends on temperature. The temperature dependence of P starts to change around 300?K. P3HT exhibits a thermal molecular motion named the ?1 relaxation process, in which the twisting motion of thiophene rings is released, in this temperature region. Thus, it can be claimed that the twisting motion of P3HT thiophene rings is one of the determining factors of the photodynamics of P in P3HT films. This finding holds true for poly(thiophene)s with different alkyl lengths and should be considered in the design and construction of highly-functionalized organic devices based on poly(thiophene)s.

SUBMITTER: Ogata Y

PROVIDER: S-EPMC4327410 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

An effect of molecular motion on carrier formation in a poly(3-hexylthiophene) film.

Ogata Yudai Y Kawaguchi Daisuke D Tanaka Keiji K

Scientific reports 20150213

Free carriers, polarons (P), in conjugated polymers play a key role in the performance of optoelectronic devices. Here, we present solid evidence that P can be predominantly generated from polaron pairs (PP) in a poly(3-hexylthiophene) (P3HT) film under zero electric field. P formation from PP strongly depends on temperature. The temperature dependence of P starts to change around 300 K. P3HT exhibits a thermal molecular motion named the α1 relaxation process, in which the twisting motion of thi ...[more]

PMID: 25678470

Similar Datasets

Understanding the Intrinsic Carrier Transport in Highly Oriented Poly(3-hexylthiophene): Effect of Side Chain Regioregularity.

Project description:The fundamental understanding of the influence of molecular structure on the carrier transport properties in the field of organic thermoelectrics (OTEs) is a big challenge since the carrier transport behavior in conducting polymers reveals average properties contributed from all carrier transport channels, including those through intra-chain, inter-chain, inter-grain, and hopping between disordered localized sites. Here, combining molecular dynamics simulations and experiments, we investigated the carrier transport properties of doped highly oriented poly(3-hexylthiophene) (P3HT) films with different side-chain regioregularity. It is demonstrated that the substitution of side chains can not only take effect on the carrier transport edge, but also on the dimensionality of the transport paths and as a result, on the carrier mobility. Conductive atomic force microscopy (C-AFM) study as well as temperature-dependent measurements of the electrical conductivity clearly showed ordered local current paths in the regular side chain P3HT films, while random paths prevailed in the irregular sample. Regular side chain substitution can be activated more easily and favors one-dimensional transport along the backbone chain direction, while the irregular sample presents the three-dimensional electron hopping behavior. As a consequence, the regular side chain P3HT samples demonstrated high carrier mobility of 2.9 ± 0.3 cm²/V·s, which is more than one order of magnitude higher than that in irregular side chain P3HT films, resulting in a maximum thermoelectric (TE) power factor of 39.1 ± 2.5 μW/mK² at room temperature. These findings would formulate design rules for organic semiconductors based on these complex systems, and especially assist in the design of high performance OTE polymers.

| S-EPMC6403984 | biostudies-literature

Enhanced Sensitivity of Gas Sensor Based on Poly(3-hexylthiophene) Thin-Film Transistors for Disease Diagnosis and Environment Monitoring.

Project description:Electronic devices based on organic thin-film transistors (OTFT) have the potential to supply the demand for portable and low-cost gadgets, mainly as sensors for in situ disease diagnosis and environment monitoring. For that reason, poly(3-hexylthiophene) (P3HT) as the active layer in the widely-used bottom-gate/bottom-contact OTFT structure was deposited over highly-doped silicon substrates covered with thermally-grown oxide to detect vapor-phase compounds. A ten-fold organochloride and ammonia sensitivity compared to bare sensors corroborated the application of this semiconducting polymer in sensors. Furthermore, P3HT TFTs presented approximately three-order higher normalized sensitivity than any chemical sensor addressed herein. The results demonstrate that while TFTs respond linearly at the lowest concentration values herein, chemical sensors present such an operating regime mostly above 2000 ppm. Simultaneous alteration of charge carrier mobility and threshold voltage is responsible for pushing the detection limit down to units of ppm of ammonia, as well as tens of ppm of alcohol or ketones. Nevertheless, P3HT transistors and chemical sensors could compose an electronic nose operated at room temperature for a wide range concentration evaluation (1-10,000 ppm) of gaseous analytes. Targeted analytes include not only biomarkers for diseases, such as uremia, cirrhosis, lung cancer and diabetes, but also gases for environment monitoring in food, cosmetic and microelectronics industries.

| S-EPMC4431216 | biostudies-literature

Selective Ammonia-Sensing Platforms Based on a Solution-Processed Film of Poly(3-Hexylthiophene) and p-Doping Tris(Pentafluorophenyl)Borane.

Project description:Here, we fabricate ammonia sensors based on organic transistors by using poly(3-hexylthiophene) (P3HT) blended with tris(pentafluorophenyl)borane (TPFB) as an active layer. As TPFB is an efficient p-type dopant for P3HT, the current level of the blend films can be easily modulated by controlling the blend ratio. The devices exhibit significantly increased on-state and off-state current levels owing to the ohmic current originated from the large number of charge carriers when the active polymer layer contains TPFB with concentrations up to 20 wt % (P3HT:TPFB = 8:2). The current is decreased at 40 wt % of TPFB (P3HT:TPFB = 6:4). The P3HT:TPFB blend with a weight ratio of 9:1 exhibits the highest sensing performances for various concentrations of ammonia. The device exhibits an increased percentage current response compared to that of a pristine P3HT device. The current response of the P3HT:TPFB (9:1) device at 100 ppm of ammonia is as high as 65.8%, 3.2 times that of the pristine P3HT (20.3%). Furthermore, the sensor based on the blend exhibits a remarkable selectivity to ammonia with respect to acetone, methanol, and dichloromethane, owing to the strong interaction between the Lewis acid (TPFB) and Lewis base (ammonia).

| S-EPMC7022764 | biostudies-literature

Optically switchable organic field-effect transistors based on photoresponsive gold nanoparticles blended with poly(3-hexylthiophene).

Project description:Interface tailoring represents a route for integrating complex functions in systems and materials. Although it is ubiquitous in biological systems--e.g., in membranes--synthetic attempts have not yet reached the same level of sophistication. Here, we report on the fabrication of an organic field-effect transistor featuring dual-gate response. Alongside the electric control through the gate electrode, we incorporated photoresponsive nanostructures in the polymeric semiconductor via blending, thereby providing optical switching ability to the device. In particular, we mixed poly(3-hexylthiophene) with gold nanoparticles (AuNP) coated with a chemisorbed azobenzene-based self-assembled monolayer, acting as traps for the charges in the device. The light-induced isomerization between the trans and cis states of the azobenzene molecules coating the AuNP induces a variation of the tunneling barrier, which controls the efficiency of the charge trapping/detrapping process within the semiconducting film. Our approach offers unique solutions to digital commuting between optical and electric signals.

| S-EPMC3411947 | biostudies-literature

Controlled synthesis of poly(3-hexylthiophene) in continuous flow.

Project description:There is an increasing demand for organic semiconducting materials with the emergence of organic electronic devices. In particular, large-area devices such as organic thin-film photovoltaics will require significant quantities of materials for device optimization, lifetime testing and commercialization. Sourcing large quantities of materials required for the optimization of large area devices is costly and often impossible to achieve. Continuous-flow synthesis enables straight-forward scale-up of materials compared to conventional batch reactions. In this study, poly(3-hexylthiophene), P3HT, was synthesized in a bench-top continuous-flow reactor. Precise control of the molecular weight was demonstrated for the first time in flow for conjugated polymers by accurate addition of catalyst to the monomer solution. The P3HT samples synthesized in flow showed comparable performance to commercial P3HT samples in bulk heterojunction solar cell devices.

| S-EPMC3740766 | biostudies-literature

Poly[(3-hexylthiophene)-block-(3-semifluoroalkylthiophene)] for polymer solar cells.

Project description:We report the synthesis of poly[(3-hexylthiophene)-block-(3-(4,4,5,5,6,6,7,7,7-nonafluoroheptyl)thiophene)], P(3HT-b-3SFT), carried out by the Grignard Metathesis Method (GRIM). The copolymers composition was determined by (1)H and (19)F NMR spectroscopies, and gel permeation chromatography (GPC). The thin films of P(3HT-b-3SFT) were investigated by ultraviolet-visible absorption spectroscopy and atomic force microscopy (AFM). We also fabricated bulk-hetero junction (BHJ) solar cells based on blends of P(3HT-b-3SFT) and [6,6]-phenyl-C(61)-butyric acid methyl ester (PCBM). Although the composition ratio of P3SFT in P(3HT-b-3SFT) was low, the influence of P3SFT on the morphology and properties of solar cells was significant. The annealing process for the BHJ solar cells induced the formation of large domains and led to poor solar cell performance. The BHJ solar cells, based on PCBM and P(3HT-b-3SFT), prepared by the non-annealing process, had a maximum power conversion efficiency of 0.84% under 100 mW/cm(2) (AM 1.5 solar illumination) in air.

| S-EPMC3100822 | biostudies-literature

Enhanced Thermoelectric Power Factor of Tensile Drawn Poly(3-hexylthiophene).

Project description:The thermoelectric power factor of a broad range of organic semiconductors scales with their electrical conductivity according to a widely obeyed power law, and therefore, strategies that permit this empirical trend to be surpassed are highly sought after. Here, tensile drawing of the conjugated polymer poly(3-hexylthiophene) (P3HT) is employed to create free-standing films with a high degree of uniaxial alignment. Along the direction of orientation, sequential doping with a molybdenum tris(dithiolene) complex leads to a 5-fold enhancement of the power factor beyond the predicted value, reaching up to 16 ?W m-1 K-2 for a conductivity of about 13 S cm-1. Neither stretching nor doping affect the glass transition temperature of P3HT, giving rise to robust free-standing materials that are of interest for the design of flexible thermoelectric devices.

| S-EPMC6344060 | biostudies-literature

Unraveling the chromophoric disorder of poly(3-hexylthiophene).

Project description:The spectral breadth of conjugated polymers gives these materials a clear advantage over other molecular compounds for organic photovoltaic applications and is a key factor in recent efficiencies topping 10%. However, why do excitonic transitions, which are inherently narrow, lead to absorption over such a broad range of wavelengths in the first place? Using single-molecule spectroscopy, we address this fundamental question in a model material, poly(3-hexylthiophene). Narrow zero-phonon lines from single chromophores are found to scatter over 200 nm, an unprecedented inhomogeneous broadening that maps the ensemble. The giant red shift between solution and bulk films arises from energy transfer to the lowest-energy chromophores in collapsed polymer chains that adopt a highly ordered morphology. We propose that the extreme energetic disorder of chromophores is structural in origin. This structural disorder on the single-chromophore level may actually enable the high degree of polymer chain ordering found in bulk films: both structural order and disorder are crucial to materials physics in devices.

| S-EPMC3780855 | biostudies-other

Functionalized Poly(3-hexylthiophene)s via Lithium-Bromine Exchange.

Project description:Poly(3-hexylthiophene) (P3HT) is one of the most extensively investigated conjugated polymers and has been employed as the active material in many devices including field-effect transistors, organic photovoltaics and sensors. As a result, methods to further tune the properties of P3HT are desirable for specific applications. Herein, we report a facile postpolymerization modification strategy to functionalize the 4-position of commercially available P3HT in two simple steps-bromination of the 4-position of P3HT (Br-P3HT) followed by lithium-bromine exchange and quenching with an electrophile. We achieved near quantitative lithium-bromine exchange with Br-P3HT, which requires over 100 thienyl lithiates to be present on a single polymer chain. The lithiated-P3HT is readily combined with functional electrophiles, resulting in P3HT derivatives with ketones, secondary alcohols, trimethylsilyl (TMS) group, fluorine, or an azide at the 4-position. We demonstrated that the azide-modified P3HT could undergo Cu-catalyzed or Cu-free click chemistry, significantly expanding the complexity of the structures that can be appended to P3HT using this method.

| S-EPMC4295809 | biostudies-other

The Impact of Aggregation on the p-Doping Kinetics of Poly(3-hexylthiophene).

Project description:The morphological effects of regioregular poly(3-hexylthiophene) (P3HT) on its p-doping kinetics with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ) in solution are studied using optical absorption spectroscopy and stopped-flow technique. Two morphological forms, solubilized (s-P3HT) and nanowhiskers (nw-P3HT), are investigated. Both P3HT solubilized and aggregated solutions show similar characteristic near-IR absorption bands for integer charge transfer products with F4-TCNQ. Kinetic analysis on p-doping of s-P3HT with F4-TCNQ indicates that the doping reaction proceeds with a single reaction mechanism that is first order in s-P3HT. The doping kinetics of P3HT aggregate solution shows two distinctive reaction mechanisms. The slow mechanism has a reaction rate constant similar to that of solubilized P3HT solution, so it likely results from s-P3HT components that are present in the aggregate solution. The fast one is assigned to the nw-P3HT component, probably due to more efficient charge delocalization in the aggregated P3HT nanostructures. Additionally, the kinetic trends of the p-doping reactions are better fitted with the consideration of a Gaussian-like distribution of reactivities from P3HT, matching the complexity of polymeric systems originating from molecular weight and morphology variations. This study highlights the importance of considering different morphological forms of conjugated polymers on their charge-transfer reaction kinetics. The knowledge gained here should be fundamentally and practically important for future chemical doping applications in organic electronic device fabrications.

| S-EPMC5646835 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data