Metrics details Understanding transport phenomena in conducting polymers (CP) is a main issue in order to optimize their performance and despite intense investigations the influence of their microstructure remains controversial By analyzing the thermoelectric measurements performed on highly oriented and non-oriented CP films we show that an Heterogeneous Oriented Structure (HOSt) model considering both ordered and disordered domains is able to account for the thermoelectric transport in CP This model unveils the key role of the crystallinity the anisotropy and the alignment degree of these domains It points out the importance of the thermal conductivity in the interpretation of the thermopower $\alpha $ and explains the frequently observed electrical conductivity $\sigma $ cut-off in the $\alpha -\sigma $ curves due to the disordered domains By varying the alignment degree depending on the orientation and the anisotropy according to the face-on or the edge-on polymers conformation the HOSt model successfully describes the overall measured thermoelectric properties by demonstrating its applicability to a wide variety of both oriented and non-oriented CP (d) Schematic illustration of the semicrystalline oriented conducting polymers made of alternating disordered (red) and ordered (blue) domains that run in (e) parallel to the rubbing direction and (f) alternate perpendicularly to the rubbing direction The equivalent electrical circuits are represented when the current/temperature gradient is parallel (||) or perpendicular ($\perp $) to the rubbing direction (g) The generalization to non-oriented conducting polymers is realized by connecting in series both parallel (e) and perpendicular (f) configurations with the corresponding geometrical factors which are related to the crystallinity $\chi $ and alignment $\gamma $ ratios as defined in the text $\gamma $ = 1 corresponds to a perfect parallel configuration (e) and $\gamma $ = 0 to a perpendicular one (f) the effective length of the parallel component as well as the perpendicular one can be varied according to $\gamma $ by preserving the overall constant length while the crystallinity changes the proportion of ordered and disordered domains by keeping constant the overall section the anisotropy and the alignment allow then to build a versatile model based on realistic key parameters the electrical G or thermal K conductances are summed in the parallel configuration and the resulting thermopower $\alpha _{\parallel }$ is a sum of each contribution $\alpha _{dis,\parallel }$ and $\alpha _{ord,\parallel }$ from the disordered and ordered domains respectively weighted by the relative electrical conductance the inverse of the conductances are summed and each thermopower contribution $\alpha _{dis,\perp }$ and $\alpha _{ord,\perp }$ is weighted by the relative thermal conductance $\chi $ changes the length as $L_{ord,\perp }=\chi L$ and $L_{dis,\perp }=(1-\chi ) L$ since the section is kept constant as $S_{ord,\perp }= S_{dis,\perp } = S$ ($\gamma = 0$) the total volume remains conserved as well as the overall both length and section in the direction parallel to the chains/rubbing: In the direction perpendicular to the rubbing this set of 3 equations describes the thermoelectric properties of non-oriented conducting polymers as well as those of oriented ones in both parallel ($\gamma =1$) and perpendicular ($\gamma =0$) directions by including variable crystallinity ratio $\chi $ anisotropy degree $\beta $ and alignment $\gamma $ We will now confront this model with experimental data gained for highly oriented PBTTT films Note that the observed behaviors typically display an enhancement of the optimum ZT by a factor 5 between the perpendicular configuration and the non-oriented one and by another factor 5 between the latter and the parallel configuration reaching the maximum value ZT$\approx $0.15 the thermopower $\alpha _{\perp }$ first follows a similar power law as $\sigma _{\perp }^{-1/4}$ for low conductivities but departs from this behavior by tending to 0 at a cut-off conductivity value of the order of 2.5 $\times $10$^3$ S/cm The $\alpha -\sigma $ correlation curve in non-oriented films lies somewhere in-between these two cases by displaying an intermediate more complex behavior which will be discussed thereafter Variation of the maximum thermoelectric figure of merit ZT$_{max}$ as a function of the crystallinity ratio $\chi $ and the alignment degree $\gamma $ as expected in the frame of the HOSt model with the inferred transport parameters ($\beta _o$ = 10) Even if the thermoelectric optimum appears when both crystallinity and alignment tend to 1 figure of merit higher than 0.1 can be reached whatever the crystallinity ($\chi $> 0.05) if $\gamma $> 0.9 and higher than 0.05 whatever the alignment if $\chi $> 0.9 A noticeable enhancement can be seen around $\chi \approx 0.1$ which increases with the alignment by exceeding 0.05 if $\gamma $> 0.8 the various correlations performed in the frame of the reported analysis are done between the transport coefficients themselves and not as a function of the doping whatever the doping efficiency our approach and the model remain valid as long as the dopants don’t alter significantly the polymers structure the model is suitable to describe the thermoelectric transport properties measured in conducting polymers prepared by other processes the HOSt model is successfully used to describe the thermoelectric properties measured in the non-oriented PBTTT film which is not prepared by high temperature rubbing some inferred characteristics should depend on the preparation processes which influence the alignment degree and the crystallinity ratio first but also the transport parameters characterizing the disordered regions demonstrates the wide applicability of the HOSt model which should even more promote the development and the use of conducting polymers in the field of organic electronics All conductivity and Seebeck coefficients were measured at ambient temperature in a glovebox In the case where the current and the temperature gradient are perpendicular to the rubbing direction, the effective electrical circuit is then composed of two elements in series with one corresponding to the disordered regions and the other to the ordered ones (see Fig. 1e and f) Each of them are characterized by their own transport coefficients a priori distinct from the ones in parallel direction with the electrical and the thermal conductances G and K and the thermopower $\alpha _{dis,\perp }$ and $\alpha _{ord,\perp }$ for disordered and ordered domains both voltages and temperatures differences are summed such as $\Delta V_{\perp } = \Delta V_{dis,\perp } + \Delta V_{ord,\perp } = \alpha _{dis,\perp } \Delta T_{dis,\perp }+ \alpha _{ord,\perp } \Delta T_{ord,\perp } = \alpha _{\perp } \Delta T_{\perp } $ which leads to an overall perpendicular thermopower as a sum of two contributions originating from disordered and ordered regions weighted by the corresponding relative temperatures differences $|I_{H,\perp }|= K_{\perp } \Delta T_{\perp } = K_{dis,\perp } \Delta T_{dis,\perp } = K_{ord,\perp } \Delta T_{ord,\perp } $ and the relative temperatures differences are given by $\frac{\Delta T_{dis/ord,\perp }}{\Delta T_{\perp }}=\frac{K_{\perp }}{ K_{dis/ord,\perp }}$ The inverse of the conductances being summed it results that the thermopower can be written as a sum of each contribution weighted by the relative thermal conductance In the case where the temperature gradient is oriented parallel to the rubbing (chain) direction ordered and disordered regions are now in parallel It follows that all the voltages as well as the temperatures differences are equal and then $\Delta V_{\parallel } = \Delta V_{dis,\parallel }= \Delta V_{ord,\parallel }$ and $\Delta T_{\parallel } = \Delta T_{dis,\parallel }= \Delta T_{ord,\parallel }$ the charge current is $|I_{C,\parallel }|= G_{\parallel } ( \Delta V_{\parallel } + \alpha _{\parallel } \Delta T_{\parallel }) = G_{dis,\parallel } ( \Delta V_{\parallel } + \alpha _{dis,\parallel } \Delta T_{\parallel }) + G_{ord,\parallel } ( \Delta V_{\parallel } + \alpha _{ord,\parallel } \Delta T_{\parallel })$ Aside from recovering that the conductances are summed the thermopower can be expressed as a sum of each contribution from disordered and ordered domains weighted by the relative electrical conductance The geometrical factors shown in Fig. 1g allow then to deduce Eq. 3 any additional datasets generated and analyzed during the current study will also be made available from the corresponding authors upon reasonable request Heeger, A. 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C 8, 16470. https://doi.org/10.1039/D0TC02828B (2020) Download references We thank the Agence Nationale de la Recherche for financial support through the project THERMOPOLYS (ANR-22-CE50-0020) region Grand’Est for the co-funding of Pablo Durand CNRS through PEPS grant Thermobody and region Centre Val-de-Loire for financial support through the project ETHERMO This work was financially supported by the European Commission through Marie Sklodowska-Curie project HORATES (GA-955837) These authors contributed equally: Patrice Limelette performed the rubbing and the transport measurements The authors declare no competing interests Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations Download citation DOI: https://doi.org/10.1038/s41598-023-48353-5 Anyone you share the following link with will be able to read this content: a shareable link is not currently available for this article Sign up for the Nature Briefing newsletter — what matters in science ®PAPERCITY ©2025 urban publishers, inc. all rights reserved terms & condition // privacy policy // sitemap Sippi & Ajay Khurana (Photo by Daniel Ortiz) Carla & Cole Dawson (Photo by Daniel Ortiz) with gala chairs Jim & Carole Looke (Photo by Daniel Ortiz) PC Moment: Three hometown health care heroes — dean of the UTHealth School of Public Health Dr. Eric Boerwinkle, Houston Methodist president and CEO Dr. Marc Boom, and Baylor College of Medicine president and CEO Dr. Paul Klotman — were honored it was no surprise that the evening drew a sellout throng of 700 and raised $1.85 million “We are grateful for Drs. 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deliver you the best experience possible while you are here Belgium - The determination that helped Justine Henin beat bigger stronger opponents time and again was fading an abrupt ending to a career in which she won seven Grand Slam singles titles and spent more than 100 weeks ranked No She announced her decision at a news conference 1½ weeks before the start of the French Open where she has won the past three titles and four overall and became the first woman to quit the sport while atop the WTA rankings "I always based everything on this motivation - this flame - that was in me Surprising as her departure was to the rest of the world After reaching the final at each Grand Slam tournament in 2006 she started to find it an ever bigger chore to pack her luggage to travel to tournaments Her legs felt heavy when she should have been dancing in the backcourt ready to turn another one of those sparkling backhands into a winner she no longer minded if an injury lingered Ever since being discovered as a child prodigy tennis was making it clear that her time was up 6-0 to Maria Sharapova in the Australian Open 6-0 to Serena Williams at the Sony Ericsson Open in April - the worst loss for a top-ranked player in nine years Then she pulled out of this week's Italian Open (retirement) all of a sudden was there as something evident," Henin said Her announcement came a day after one of the greatest female golfers in history said she's quitting: Annika Sorenstam owner of 10 major titles and one of six women to complete a career Grand Slam in her sport and I feel strong and relieved that I could take this decision," she said In addition to her four French Open titles except for a seven-week period last year when Sharapova held the top spot and won nearly $20 million in career prize money who lost to Henin in a contentious 2003 French Open quarterfinal The only Grand Slam title to elude Henin is Wimbledon "Winning Wimbledon would not make me happier than I am," she said Winning again at Roland Garros would make no difference no matter how much that event means to her Henin dedicated her first victory there to her mother it capped a reunion with her father and siblings from whom she'd been estranged for several years and I am going to keep that feeling forever now," she said she had to figure out how to deal with foes who could hit the ball harder "She always challenged herself to play her best tennis no matter what the circumstances so I think that was really what made her best," Venus Williams said "Justine Henin will be remembered as one of the all-time great champions in women's tennis and a woman who made up for her lack of size with a will to win and fighting spirit that was second to none," WTA Tour CEO Larry Scott said "It is rare that an athlete leaves at the very top of her game in this day and age but Justine has always played by her own rules Henin was away from the tour for months at a time in 2004 and 2005 because of an energy-sapping blood virus and assorted injuries she divorced from Pierre-Yves Hardenne and dropped his last name Henin said she had finally found a balance in her life between personal self-fulfillment and doggedly pursuing tennis titles Perhaps she took note when Kim Clijsters - another Belgian who was ranked No 1 and won a Grand Slam title - retired at 23 last year Clijsters has since married and become a mother Dressed in a simple white T-shirt and jeans Henin spoke in French for nine minutes before taking questions Wednesday She never lost her composure and held the microphone firmly The news conference was at the Justine N1 academy in a village about 20 miles outside of Brussels It has a smattering of her beloved clay courts where she wants to train and coach youngsters Metrics details By directly converting heat into electricity thermoelectric effects provide a unique physical process from heat waste to energy harvesting Requiring the highest possible power factor defined as α2σ with the thermopower α and the electrical conductivity σ such a technology necessitates the best knowledge of transport phenomena in order to be able to control and optimize both α and σ While conducting polymers have already demonstrated their great potentiality with enhanced thermoelectric performance the full understanding of the transport mechanisms in these compounds is still lacking Here we show that the thermoelectric properties of one of the most promising conducting polymer the poly(3,4-ethylenedioxythiophene) doped with tosylate ions (PEDOT-Tos) follows actually a very generic behavior with a scaling relation as α ∝ σ−1/4 Whereas conventional transport theories have failed to explain such an exponent we demonstrate that it is in fact a characteristic of massless pseudo-relativistic quasiparticles scattered by unscreened ionized impurities it is sizably enhanced in oriented conducting polymers by approaching $1\,W\,{m}^{-1}\,{K}^{-1}$ Such a value highlights the potentiality of the conducting polymers in the context of thermoelectric applications even if thermal conductivity characterizations are required in order to precise ZT the origin of the exponent s can be discussed as well as the parameters influencing it The general formulations of $\sigma $ and $\alpha $ can be deduced in terms of Fermi integrals and yield to scaling relations which hold in either non degenerate or degenerate regimes the relaxation time approximation allows to consider two scattering mechanisms for non relativistic and Dirac fermions These calculations allow finally to discuss the different inferred exponents s consistent with the scaling behavior between $\alpha $ and $\sigma $ as observed experimentally in many conducting polymers with the energy dependent relaxation time ${\tau }_{E}$ the density of states ${g}_{E}$ and the Fermi-Dirac statistic ${f}_{E}$ T being the temperature and $\mu $ the chemical potential $\nu $ and $\gamma $ the exponents of the relaxation time the velocity and the density of states respectively their energy dependence can be made explicit such as: the characteristic energies ${E}_{\tau }$ ${v}_{0}$ and ${g}_{0}$ have been introduced in order to focus on energy dependence It follows that the kinetic coefficients can be written as: The electrical conductivity can then be expressed as an integral over quasiparticles reduced energy $\varepsilon =E/{k}_{B}T$ the thermopower can be more conveniently rewritten below where the reduced chemical potential $\tilde{\mu }=\mu /{k}_{B}T$ has been introduced: We also mention that the same exponent is expected for acoustic phonons scattering but in the low temperature regime namely below the Debye temperature which is usually well below the room temperature in conducting polymers the density of states is declined below as a function of the D dimensionality of the quasiparticles the density of states can be reformulated by introducing the D-dimensional density of fermions ${n}_{D}$ and the Fermi energy ${E}_{F}$ This leads to a compact form of the Dirac (relativistic) fermions density of states ${g}_{D,E}^{r}$ which can be more easily compared to the non relativistic free fermions density of states ${g}_{D,E}^{nr}$ Our both results and analysis make therefore an unexpected connection between Dirac materials and conducting polymers due to the scaling relation the thermal power factor is expected to vary with the reduced chemical potential with the exponent s-2 as discussed in the Supplementary Information Such a dependence demonstrates thus that the exponent s = 4 favors higher thermal power factor than s = 3 namely that Dirac fermions could favor better thermoelectric efficiency than conventional electrons The iron tosylate solution (40% in butanol) was purchased from Heraeus (Clevios-40) while EDOT and pyridine were purchased from Sigma-Aldrich Pyridine was added in the Fe(Tos)3 solution in order to reach a ratio of 0.5 mol of pyridine per 1 mol of iron tosylate This oxidant solution was stirred for 24 h at 0 °C The mixture was then cooling down to −30 °C Afterwards the EDOT monomer was added to the oxidant solution with an oxidant-to-monomer ratio of 2.3:1 The mixture was stirred continuously at −30 °C for 3 h The resulting solution was spin-coated on glass substrates previously washed with aqua regia then acetone in an ultrasonic bath it was annealed on a hot plate at 70 °C during 20 mn to initiate the polymerization reaction by evaporating butanol and pyridine In order to remove the remaining oxidant and the unreacted monomers the films were washed several times with distilled water and removed from the substrates to be put back on substrates to avoid side effect and to improve homogeneity The PEDOT-Tos films were further dried under primary vacuum at 50 °C during 24 h Thereby we obtain PEDOT-Tos films with a thickness of 500 ± 10 nm with a spinning speed of 500 rpm and an acceleration of 100 rpm/s or 1 μm ± 10 nm with a spinning speed of 100 rpm and an acceleration of 100 rpm/s The reduction of PEDOT-Tos was done by immersion of the sample in ethanolamine alcoholic solutions of different concentrations (from pure ethanolamine to 105 times diluted in ethanol) for 24 h then dried under primary vacuum at 50 °C for 24 h Polymers have been characterized with infrared spectroscopy UV-Vis-NIR spectroscopy and X-ray diffraction Infrared analysis has been performed with a Perkin-Elmer Spectrum-One FTIR over the range of 1800–800 cm−1. All spectra show the typical bands for PEDOT-Tos with variations depending the concentration of the chemical treatment (Fig. S2 in the Supplementary Information) The persistence of the signal of tosylate chemical functions for all basic treatments shows that the tosylate is not removed from the films but only protonated and become p-toluenesulfonic acid No remaining iron from Fe(Tos)3 was observed it is possible to control the oxidation level of PEDOT-Tos by controlling the concentration of the reducing agent in the treatment solution A 2 peaks structure is found at 6.5° and 12.2° dependent on the reduction level They appear better defined in the PEDOT-Tos as-synthesized rather than in those treated with high ethanolamine concentration The decrease of the peaks seems to indicate besides the dedoping an alteration of the nanostructural organization which leads to a film less crystallized Note that a missing peak at 25° usually ascribed to the face to face interchain stacking distance between thiophene rings can be recovered in superimposed films from the same synthesis This suggests a face-on organization of the chains towards the glass substrate In order to perform thermoelectric measurements on these films 100 nm gold electrodes have been deposited through a mask to ensure low contact resistances by using silver paste Both the electrical conductivity and the thermopower measurements have been performed under a maintained secondary vacuum (P < 10−5 mbar) using a four points configuration with a Physical Properties Measurements System from Quantum Design Temperature rise of 1% has been applied in order to measure the thermopower and an electrical current of 10 μA has been used for electrical conductivity measurements The current intensity has been chosen to both stay in ohmic conditions and minimize Joule effect in the material Mahan, G. 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Electron. 15, 3087–3095, https://doi.org/10.1016/j.orgel.2014.09.012 (2014) Download references The authors acknowledge support from the ANR Anisotherm (no synthesized the PEDOT-Tos samples with the assistance of B.S he realized the IR and UV spectroscopies as well as the XRD measured the thermopower and the electrical conductivity with the assistance of P.L who performed the transport calculations and interpret the data wrote the Methods section while the main text and the Supplementary Information have been written by P.L Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations Reprints and permissions Download citation DOI: https://doi.org/10.1038/s41598-020-64951-z Please enable JS and disable any ad blocker ®PAPERCITY ©2025 urban publishers, inc. all rights reserved terms & condition // privacy policy // sitemap Contemporary North Carolina-based clothing brand Marie Oliver fêted influential Houston women and friends of the brand in high style at a dinner party held at Adair Downtown the brand’s agency Savannah Engel PR reached out to guests a list curated with the help of Natalie Steen of The Nat Note and Alice Adair in advance of the event and informed them Marie Oliver was gifting them with a dress or skirt of their choosing from the fall 2022 collection exciting way to show how versatile the contemporary brand’s clothes truly are as each woman put her own style’s spin on the looks The bevy of well-dressed ladies enjoyed margaritas and conversation and the sounds of a mariachi band before a seated taco and fajita dinner at the dramatic long table in the beautiful Adair Downtown space After Evenson made lovely remarks to her new Texan friends the crew were invited to go outside on the patio for more drinks and a few jovial swings at a custom piñata bedecked in Marie Oliver cheeky plastic rings and candy flew alongside abundant laughter Marie Oliver generously provided Lyft codes to and from the event and gifted guests sets of gorgeous Marie Oliver-printed dinner napkins