This page has only limited features, please log in for full access.
A series of well-defined (polyisoprene)2(polystyrene), I2S, single graft copolymers with similar total molecular weights but different compositions, fPS , were blended with a low molecular weight polyisoprene homopolymer matrix at a constant concentration 2 wt%, and the micellar characteristics were studied by small-angle x-ray scattering. To investigate the effect of macromolecular architecture on the formation and characteristics of micelles, the results on the single graft copolymers were compared with those of the corresponding linear polystyrene-b-polyisoprene diblock copolymers, SI. The comparison reveals that the polystyrene core chains are more stretched in the case of graft copolymer micelles. Stretching turned out to be purely a result of the architecture due to the second polyisoprene block in the corona. The micellization of a (polystyrene)2(polyisoprene), S2I, graft copolymer was also studied, and the comparison with the results of the corresponding I2S and SI copolymers emphasizes the need for a critical core volume rather than a critical length of the core-forming block, in order to have stable micelles. Finally, the absence of micellization in the case of the I2S copolymer with the highest polystyrene volume fraction is discussed. For this sample, macrophase separation occurs, with polyisoprene cylinders formed in the copolymer-rich domains of the phase-separated blends.
Eleni Pavlopoulou; Kiriaki Chrissopoulou; Stergios Pispas; Nikos Hadjichristidis; Spiros Anastasiadis. The Micellization of Well-Defined Single Graft Copolymers in Block Copolymer/Homopolymer Blends. Polymers 2021, 13, 833 .
AMA StyleEleni Pavlopoulou, Kiriaki Chrissopoulou, Stergios Pispas, Nikos Hadjichristidis, Spiros Anastasiadis. The Micellization of Well-Defined Single Graft Copolymers in Block Copolymer/Homopolymer Blends. Polymers. 2021; 13 (5):833.
Chicago/Turabian StyleEleni Pavlopoulou; Kiriaki Chrissopoulou; Stergios Pispas; Nikos Hadjichristidis; Spiros Anastasiadis. 2021. "The Micellization of Well-Defined Single Graft Copolymers in Block Copolymer/Homopolymer Blends." Polymers 13, no. 5: 833.
The presence of excited-states and charge-separated species was identified through UV and visible laser pump and visible/near-infrared probe femtosecond transient absorption spectroscopy in spin coated films of poly[N-9″-heptadecanyl-2,7-carbazole-alt-5,5-(4,7-di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT) nanoparticles and mesoparticles. Optical gain in the mesoparticle films is observed after excitation at both 400 and 610 nm. In the mesoparticle film, charge generation after UV excitation appears after around 50 ps, but little is observed after visible pump excitation. In the nanoparticle film, as for a uniform film of the pure polymer, charge formation was efficiently induced by UV excitation pump, while excitation of the low energetic absorption states (at 610 nm) induces in the nanoparticle film a large optical gain region reducing the charge formation efficiency. It is proposed that the different intermolecular interactions and molecular order within the nanoparticles and mesoparticles are responsible for their markedly different photophysical behavior. These results therefore demonstrate the possibility of a hitherto unexplored route to stimulated emission in a conjugated polymer that has relatively undemanding film preparation requirements.
Mark Geoghegan; Marta Mróz; Chiara Botta; Laurie Parrenin; Cyril Brochon; Eric Cloutet; Eleni Pavlopoulou; Georges Hadziioannou; Tersilla Virgili. Optical Gain in Semiconducting Polymer Nano and Mesoparticles. Molecules 2021, 26, 1138 .
AMA StyleMark Geoghegan, Marta Mróz, Chiara Botta, Laurie Parrenin, Cyril Brochon, Eric Cloutet, Eleni Pavlopoulou, Georges Hadziioannou, Tersilla Virgili. Optical Gain in Semiconducting Polymer Nano and Mesoparticles. Molecules. 2021; 26 (4):1138.
Chicago/Turabian StyleMark Geoghegan; Marta Mróz; Chiara Botta; Laurie Parrenin; Cyril Brochon; Eric Cloutet; Eleni Pavlopoulou; Georges Hadziioannou; Tersilla Virgili. 2021. "Optical Gain in Semiconducting Polymer Nano and Mesoparticles." Molecules 26, no. 4: 1138.
Herein, we investigate the technologically relevant blend of the ferroelectric polymer poly(vinylidene fluoride-co-trifluoroethylene), P(VDF-co-TrFE), with the semiconducting polymer poly(3-hexylthiophene), P3HT, by means of a combination of scanning probe microscopy techniques, namely atomic force microscopy, conductive force microscopy, kelvin probe force microscopy, and piezoresponse force microscopy. This combination proves to be a powerful tool for the non-destructive morphological reconstruction of multi-functional nano-structured thin films, as those under study. Each modality allows discerning the two blend constituents based on their functionality, and, additionally, probes layers of different thickness with respect to the film surface. The depth-dependent information that is collected allows a qualitative reconstruction of the blend’s composition and morphology both in-plane and out-of-plane of the film. We demonstrate that P3HT exhibits the tendency to reside the film surface at an almost constant composition of 15%, independent of blend’s composition. Increasing the P3HT content in the blend results in the segregation of P3HT at the upper layers of the films, partially buried below a P(VDF-co-TrFE) superficial layer. The depletion of P3HT from the substrate/film interface is reflected by the poor existence of conducting pathways that connect the top and bottom planes of the film. The three-dimensional morphology of this polymer blend that is revealed thanks to the employed techniques deviates substantially from the ideal morphology proposed for the efficient performance of the targeted memory devices.
N. Spampinato; G. Pecastaings; M. Maglione; G. Hadziioannou; E. Pavlopoulou. Non-destructive depth-dependent morphological characterization of ferroelectric:semiconducting polymer blend films. Colloid and Polymer Science 2021, 299, 551 -560.
AMA StyleN. Spampinato, G. Pecastaings, M. Maglione, G. Hadziioannou, E. Pavlopoulou. Non-destructive depth-dependent morphological characterization of ferroelectric:semiconducting polymer blend films. Colloid and Polymer Science. 2021; 299 (3):551-560.
Chicago/Turabian StyleN. Spampinato; G. Pecastaings; M. Maglione; G. Hadziioannou; E. Pavlopoulou. 2021. "Non-destructive depth-dependent morphological characterization of ferroelectric:semiconducting polymer blend films." Colloid and Polymer Science 299, no. 3: 551-560.
Electronic materials that can self-organize in vivo and form functional components along the tissue of interest can result in a seamless integration of the bioelectronic interface. Previously, we presented in vivo polymerization of the conjugated oligomer ETE-S in plants, forming conductors along the plant structure. The EDOT–thiophene–EDOT trimer with a sulfonate side group polymerized due to the native enzymatic activity of the plant and integrated within the plant cell wall. Here, we present the synthesis of three different conjugated trimers based on thiophene and EDOT or purely EDOT trimers that are able to polymerize enzymatically in physiological pH in vitro as well as in vivo along the roots of living plants. We show that by modulating the backbone and the side chain, we can tune the electronic properties of the resulting polymers as well as their localization and penetration within the root. Our work paves the way for the rational design of electronic materials that can self-organize in vivo for spatially controlled electronic functionalization of living tissue.
Daniele Mantione; Emin Istif; Gwennael Dufil; Lorenzo Vallan; Daniela Parker; Cyril Brochon; Eric Cloutet; Georges Hadziioannou; Magnus Berggren; Eleni Stavrinidou; Eleni Pavlopoulou. Thiophene-Based Trimers for In Vivo Electronic Functionalization of Tissues. ACS Applied Electronic Materials 2020, 2, 4065 -4071.
AMA StyleDaniele Mantione, Emin Istif, Gwennael Dufil, Lorenzo Vallan, Daniela Parker, Cyril Brochon, Eric Cloutet, Georges Hadziioannou, Magnus Berggren, Eleni Stavrinidou, Eleni Pavlopoulou. Thiophene-Based Trimers for In Vivo Electronic Functionalization of Tissues. ACS Applied Electronic Materials. 2020; 2 (12):4065-4071.
Chicago/Turabian StyleDaniele Mantione; Emin Istif; Gwennael Dufil; Lorenzo Vallan; Daniela Parker; Cyril Brochon; Eric Cloutet; Georges Hadziioannou; Magnus Berggren; Eleni Stavrinidou; Eleni Pavlopoulou. 2020. "Thiophene-Based Trimers for In Vivo Electronic Functionalization of Tissues." ACS Applied Electronic Materials 2, no. 12: 4065-4071.
Vertical inhomogeneity found in vapour phase polymerized thin films of the conducting polymer PEDOT:Tos.
Shangzhi Chen; Ioannis Petsagkourakis; Nicoletta Spampinato; Chaoyang Kuang; Xianjie Liu; Robert Brooke; Evan S. H. Kang; Mats Fahlman; Xavier Crispin; Eleni Pavlopoulou; Magnus P. Jonsson. Unraveling vertical inhomogeneity in vapour phase polymerized PEDOT:Tos films. Journal of Materials Chemistry A 2020, 8, 18726 -18734.
AMA StyleShangzhi Chen, Ioannis Petsagkourakis, Nicoletta Spampinato, Chaoyang Kuang, Xianjie Liu, Robert Brooke, Evan S. H. Kang, Mats Fahlman, Xavier Crispin, Eleni Pavlopoulou, Magnus P. Jonsson. Unraveling vertical inhomogeneity in vapour phase polymerized PEDOT:Tos films. Journal of Materials Chemistry A. 2020; 8 (36):18726-18734.
Chicago/Turabian StyleShangzhi Chen; Ioannis Petsagkourakis; Nicoletta Spampinato; Chaoyang Kuang; Xianjie Liu; Robert Brooke; Evan S. H. Kang; Mats Fahlman; Xavier Crispin; Eleni Pavlopoulou; Magnus P. Jonsson. 2020. "Unraveling vertical inhomogeneity in vapour phase polymerized PEDOT:Tos films." Journal of Materials Chemistry A 8, no. 36: 18726-18734.
The interfacial energetics are known to play a crucial role in organic electronic devices. However, their effects in organic thermoelectrics remain to be elucidated. In this work we optimize the output power density of an organic thermoelectric generator (OTEG) at ambient atmosphere to record high values, by varying the work function of the metal contacts. We find that the effect is linked to extended gradients of doping states, which are induced by humidity and reside inside the organic layer oriented perpendicular to the metal contacts. The thermovoltage, arising from this contact phenomenon alone, reaches a magnitude similar to that of the Seebeck voltage of the conducting polymer itself, thereby providing a major contribution to the resulting thermoelectric performance. With this work, we put a new emphasis on the importance of the metal-polymer interface in thermoelectrics. The overall output performance can be greatly improved by fine-tuning the interfacial energetics, which then provides an attractive complementing route for enhancing the performance of OTEGs.
I. Petsagkourakis; S. Riera-Galindo; Tero-Petri Ruoko; Xenofon Strakosas; Eleni Pavlopoulou; Xianjie Liu; Slawomir Braun; Nara Kim; S. Lienemann; V. Gueskine; Georges Hadziioannou; Magnus Berggren; Mats Fahlman; Simone Fabiano; Klas Tybrandt; Xavier Crispin. Ultra-High Performance Organic Thermoelectric Generators through Interfacial Doping Gradients. 2020, 1 .
AMA StyleI. Petsagkourakis, S. Riera-Galindo, Tero-Petri Ruoko, Xenofon Strakosas, Eleni Pavlopoulou, Xianjie Liu, Slawomir Braun, Nara Kim, S. Lienemann, V. Gueskine, Georges Hadziioannou, Magnus Berggren, Mats Fahlman, Simone Fabiano, Klas Tybrandt, Xavier Crispin. Ultra-High Performance Organic Thermoelectric Generators through Interfacial Doping Gradients. . 2020; ():1.
Chicago/Turabian StyleI. Petsagkourakis; S. Riera-Galindo; Tero-Petri Ruoko; Xenofon Strakosas; Eleni Pavlopoulou; Xianjie Liu; Slawomir Braun; Nara Kim; S. Lienemann; V. Gueskine; Georges Hadziioannou; Magnus Berggren; Mats Fahlman; Simone Fabiano; Klas Tybrandt; Xavier Crispin. 2020. "Ultra-High Performance Organic Thermoelectric Generators through Interfacial Doping Gradients." , no. : 1.
The pursuit for novelty in the field of (bio)electronics demands for new and better performing (semi)conductive materials. Since the discovery of poly(3,4-ethylenedioxythiophene) (PEDOT) – the ubiquitous golden standard – many studies have focused on its applications, but only few on its structural modification and/or functionalization. This lack of structural variety strongly limits the versatility of PEDOT, thus hampering the development of novel PEDOT-based materials. In this paper, we present a short and simple strategy for introducing an aldehyde functionality in thiophene-based semiconducting polymers. First, through a two steps synthesis, an EDOT-aldehyde derivative was prepared and polymerized, both chemically and electrochemically. Next, to overcome the inability of thiophene-aldehyde to be polymerized by any means, we synthesized a trimer, in which thiophene-aldehyde is enclosed between two EDOT groups. The successful chemical and electrochemical polymerization of this new trimer is presented. The polymers suspensions were characterized by UV-Vis-NIR spectroscopy, while the corresponding films by FT-IR and four-point-probe (FPP) conductivity measurements. Afterwards, insoluble semiconducting films were formed by using ethylenediamine as crosslinker, demonstrating in this way the suitability of the aldehyde group for the easy chemical modification of our material. The efficient reactivity conferred by aldehyde groups was also exploited for grafting fluorescent polyamine nanoparticles on the films surface, creating a fluorescent semiconducting polymer film. The films prepared by electropolymerization, as shown by means of a sonication test, exhibit strong surface adhesion on pristine indium tin oxide (ITO). This property paves the way for the application of these polymers as conductive electrodes for interfacing with living organisms. Thanks to the high reactivity of the aldehyde group, the aldehyde-bearing thiophene-based polymers prepared herein are extremely valuable for numerous applications requiring the facile incorporation of a functional group on thiophene, such as the functionalization with labile molecules (thermo-, photo- and electro-labile, pH sensitive, etc.).
Emin Istif; Daniele Mantione; Lorenzo Vallan; Georges Hadziioannou; Cyril Brochon; Eric Cloutet; Eleni Pavlopoulou. Thiophene-Based Aldehyde Derivatives for Functionalizable and Adhesive Semiconducting Polymers. ACS Applied Materials & Interfaces 2020, 12, 8695 -8703.
AMA StyleEmin Istif, Daniele Mantione, Lorenzo Vallan, Georges Hadziioannou, Cyril Brochon, Eric Cloutet, Eleni Pavlopoulou. Thiophene-Based Aldehyde Derivatives for Functionalizable and Adhesive Semiconducting Polymers. ACS Applied Materials & Interfaces. 2020; 12 (7):8695-8703.
Chicago/Turabian StyleEmin Istif; Daniele Mantione; Lorenzo Vallan; Georges Hadziioannou; Cyril Brochon; Eric Cloutet; Eleni Pavlopoulou. 2020. "Thiophene-Based Aldehyde Derivatives for Functionalizable and Adhesive Semiconducting Polymers." ACS Applied Materials & Interfaces 12, no. 7: 8695-8703.
The technological interest in developing novel functional nano-objects which exhibit new properties arising from their nanoscopic nature is undoubtful. Although bulk ZnO is considered to be non-ferroelectric, herein the ferroelectric behavior of un-doped and self-standing ZnO nanoparticles is reported for the first time. The nanoparticles (NPs) under study are synthesized by an organometallic approach. When dispersed in a PMMA dielectric matrix clear polarizations loops and antisymmetric switching currents are recorded for the NPs with the larger volume, in coherence with the significant polar response of these NPs in solution, measured by polarization-resolved second harmonic scattering (SHS) experiments. Structural characterizations reveal that ferroelectricity is related to the appearance of a new hexagonal crystalline phase, its unit cell being swelled with respect to the well-known wurtzite ZnO cell. The volume fraction of this new phase, the polar SHS response and the amount of ferroelectric polarization response are all linearly linked, underlining the consistency between these complementary physical characterizations.
Jon Maiz; Pauline Loxq; Pierre Fau; Katia Fajerwerg; Myrtil L. Kahn; Guillaume Fleury; Georges Hadziioannou; Guillaume Guegan; Jérôme Majimel; Mario Maglione; Vincent Rodriguez; Eleni Pavlopoulou. Ferroelectricity in Undoped ZnO Nanorods. The Journal of Physical Chemistry C 2019, 123, 29436 -29444.
AMA StyleJon Maiz, Pauline Loxq, Pierre Fau, Katia Fajerwerg, Myrtil L. Kahn, Guillaume Fleury, Georges Hadziioannou, Guillaume Guegan, Jérôme Majimel, Mario Maglione, Vincent Rodriguez, Eleni Pavlopoulou. Ferroelectricity in Undoped ZnO Nanorods. The Journal of Physical Chemistry C. 2019; 123 (48):29436-29444.
Chicago/Turabian StyleJon Maiz; Pauline Loxq; Pierre Fau; Katia Fajerwerg; Myrtil L. Kahn; Guillaume Fleury; Georges Hadziioannou; Guillaume Guegan; Jérôme Majimel; Mario Maglione; Vincent Rodriguez; Eleni Pavlopoulou. 2019. "Ferroelectricity in Undoped ZnO Nanorods." The Journal of Physical Chemistry C 123, no. 48: 29436-29444.
We investigated the impact of Singly Occupied Molecular Orbital (SOMO) energy on the n-doping efficiency of benzimidazole-derivatives. By designing and synthesizing a series of new air-stable benzimidazole-based dopants with different SOMO energy levels, we demonstrated that an increase of the dopant SOMO energy by only ~0.3 eV enhances the electrical conductivity of a benchmark electron-transporting naphtha-lenediimide-bithiophene polymer by more than one order of magnitude. By combining electrical, X-ray diffraction, and electron paramagnetic resonance measurements with density functional theory calculations and analytical transport simulations, we quantitatively characterized the conductivity, Seebeck coefficient, spin density, crystallinity of the doped polymer as a function of the dopant SOMO energy. Our findings strongly indicate that charge and energy transport are dominated by the (relative) position of the SOMO level, whereas morphological differences appear to play a lesser role. These results set molecular-design guidelines for next-generation n-type dopants.
Sergi Riera-Galindo; Alessio Orbelli Biroli; Alessandra Forni; Yuttapoom Puttisong; Francesca Tessore; Maddalena Pizzotti; Eleni Pavlopoulou; Eduardo Solano; Suhao Wang; Gang Wang; Tero-Petri Ruoko; Weimin M. Chen; Martijn Kemerink; Magnus Berggren; Gabriele Di Carlo; Simone Fabiano. Impact of Singly Occupied Molecular Orbital Energy on the n-Doping Efficiency of Benzimidazole Derivatives. ACS Applied Materials & Interfaces 2019, 11, 37981 -37990.
AMA StyleSergi Riera-Galindo, Alessio Orbelli Biroli, Alessandra Forni, Yuttapoom Puttisong, Francesca Tessore, Maddalena Pizzotti, Eleni Pavlopoulou, Eduardo Solano, Suhao Wang, Gang Wang, Tero-Petri Ruoko, Weimin M. Chen, Martijn Kemerink, Magnus Berggren, Gabriele Di Carlo, Simone Fabiano. Impact of Singly Occupied Molecular Orbital Energy on the n-Doping Efficiency of Benzimidazole Derivatives. ACS Applied Materials & Interfaces. 2019; 11 (41):37981-37990.
Chicago/Turabian StyleSergi Riera-Galindo; Alessio Orbelli Biroli; Alessandra Forni; Yuttapoom Puttisong; Francesca Tessore; Maddalena Pizzotti; Eleni Pavlopoulou; Eduardo Solano; Suhao Wang; Gang Wang; Tero-Petri Ruoko; Weimin M. Chen; Martijn Kemerink; Magnus Berggren; Gabriele Di Carlo; Simone Fabiano. 2019. "Impact of Singly Occupied Molecular Orbital Energy on the n-Doping Efficiency of Benzimidazole Derivatives." ACS Applied Materials & Interfaces 11, no. 41: 37981-37990.
The photophysics of water and propan-1-ol suspensions of poly [N-9”-heptadecanyl-2,7-carbazole-alt−5,5-(4,7-di-2-thienyl-2′,1′,3′- benzothiadiazole)] (PCDTBT) nanoparticles and mesoparticles has been studied by ultrafast spectroscopy. High molar mass polymer (HMM > 20 kg/mol) forms nanoparticles with around 50 nm diameter via mini-emulsion post-polymerization, while low molar mass (LMM < 5 kg/mol) polymer prepared by dispersion polymerization results in particles with a diameter of almost one order of magnitude larger (450 ± 50 nm). In this study, the presence of excited-states and charge separated species was identified through UV pump and visible/near-infrared probe femtosecond transient absorption spectroscopy. A different behavior for the HMM nanoparticles has been identified compared to the LMM mesoparticles. The nanoparticles exhibit typical features of an energetically disordered conjugated polymer with a broad density of states, allowing for delayed spectral relaxation of excited states, while the mesoparticles show a J-aggregate-like behavior where interchain interactions are less efficient. Stimulated emission in the red-near infrared region has been found in the mesoparticles which indicates that they present a more energetically ordered system.
Tersilla Virgili; Chiara Botta; Marta M. Mróz; Laurie Parrenin; Cyril Brochon; Eric Cloutet; Eleni Pavlopoulou; Georges Hadziioannou; Mark Geoghegan. Size-Dependent Photophysical Behavior of Low Bandgap Semiconducting Polymer Particles. Frontiers in Chemistry 2019, 7, 409 .
AMA StyleTersilla Virgili, Chiara Botta, Marta M. Mróz, Laurie Parrenin, Cyril Brochon, Eric Cloutet, Eleni Pavlopoulou, Georges Hadziioannou, Mark Geoghegan. Size-Dependent Photophysical Behavior of Low Bandgap Semiconducting Polymer Particles. Frontiers in Chemistry. 2019; 7 ():409.
Chicago/Turabian StyleTersilla Virgili; Chiara Botta; Marta M. Mróz; Laurie Parrenin; Cyril Brochon; Eric Cloutet; Eleni Pavlopoulou; Georges Hadziioannou; Mark Geoghegan. 2019. "Size-Dependent Photophysical Behavior of Low Bandgap Semiconducting Polymer Particles." Frontiers in Chemistry 7, no. : 409.
Experimental and theoretical simulations of high conductive vapour phased synthesized poly(3,4-ethylenedioxythiophene) for transparent conductor applications.
Robert Brooke; Juan Felipe Franco-Gonzalez; Kosala Wijeratne; Eleni Pavlopoulou; Daniela Galliani; Xianjie Liu; Roudabeh Valiollahi; Igor V. Zozoulenko; Xavier Crispin. Vapor phase synthesized poly(3,4-ethylenedioxythiophene)-trifluoromethanesulfonate as a transparent conductor material. Journal of Materials Chemistry A 2018, 6, 21304 -21312.
AMA StyleRobert Brooke, Juan Felipe Franco-Gonzalez, Kosala Wijeratne, Eleni Pavlopoulou, Daniela Galliani, Xianjie Liu, Roudabeh Valiollahi, Igor V. Zozoulenko, Xavier Crispin. Vapor phase synthesized poly(3,4-ethylenedioxythiophene)-trifluoromethanesulfonate as a transparent conductor material. Journal of Materials Chemistry A. 2018; 6 (43):21304-21312.
Chicago/Turabian StyleRobert Brooke; Juan Felipe Franco-Gonzalez; Kosala Wijeratne; Eleni Pavlopoulou; Daniela Galliani; Xianjie Liu; Roudabeh Valiollahi; Igor V. Zozoulenko; Xavier Crispin. 2018. "Vapor phase synthesized poly(3,4-ethylenedioxythiophene)-trifluoromethanesulfonate as a transparent conductor material." Journal of Materials Chemistry A 6, no. 43: 21304-21312.
The functional properties of P(VDF-co-TrFE) are strongly dependent on its structure, which, in turn, depends on processing conditions applied. In this work we investigate the P(VDF-co-TrFE) processing-structure-function relationships, in order to find the thermal conditions that result in optimum ferroelectric performance in thin film configuration. Our results show that annealing temperature affects mostly the remnant polarization value, Pr, while annealing time has a severe effect on the coercive field, Ec. An optimized ferroelectric functionality, in terms of high Pr of about 90 mC/m2 and low Ec of 50 MV/m, is achieved and rationalized through structural analysis by means of GIWAXS. The best performing structure exhibits a high degree of crystallinity, a preferential orientation of the crystallites with the polymer chains parallel to the substrate and the occurrence of three ferroelectric phases. A deconvolution study demonstrates the presence of a moderately unstable ferroelectric phase that is designated to facilitate ferroelectric switching. Our findings show that a single step of 15 min annealing at 135 °C leads to high performance P(VDF-co-TrFE) structure, proving that the 2 h-long annealing step that is traditionally applied is not necessary.
Nicoletta Spampinato; Jon Maiz; Giuseppe Portale; Mario Maglione; Georges Hadziioannou; Eleni Pavlopoulou. Enhancing the ferroelectric performance of P(VDF-co-TrFE) through modulation of crystallinity and polymorphism. Polymer 2018, 149, 66 -72.
AMA StyleNicoletta Spampinato, Jon Maiz, Giuseppe Portale, Mario Maglione, Georges Hadziioannou, Eleni Pavlopoulou. Enhancing the ferroelectric performance of P(VDF-co-TrFE) through modulation of crystallinity and polymorphism. Polymer. 2018; 149 ():66-72.
Chicago/Turabian StyleNicoletta Spampinato; Jon Maiz; Giuseppe Portale; Mario Maglione; Georges Hadziioannou; Eleni Pavlopoulou. 2018. "Enhancing the ferroelectric performance of P(VDF-co-TrFE) through modulation of crystallinity and polymorphism." Polymer 149, no. : 66-72.
Emission of the synthesized polysquaraine (left) and CIE 1931 color space chromaticity diagram of the corresponding OLED (right).
Guillaume Garbay; Tiphaine Tailliez; Eleni Pavlopoulou; Jules Oriou; Mickael Bezirdjoglou; Georges Hadziioannou; Eric Cloutet; Cyril Brochon. Triaryl-1,4-diamine-based polysquaraines: effect of co-solvent and monomer insertion on optoelectronic properties. Polymer Chemistry 2018, 9, 1288 -1292.
AMA StyleGuillaume Garbay, Tiphaine Tailliez, Eleni Pavlopoulou, Jules Oriou, Mickael Bezirdjoglou, Georges Hadziioannou, Eric Cloutet, Cyril Brochon. Triaryl-1,4-diamine-based polysquaraines: effect of co-solvent and monomer insertion on optoelectronic properties. Polymer Chemistry. 2018; 9 (11):1288-1292.
Chicago/Turabian StyleGuillaume Garbay; Tiphaine Tailliez; Eleni Pavlopoulou; Jules Oriou; Mickael Bezirdjoglou; Georges Hadziioannou; Eric Cloutet; Cyril Brochon. 2018. "Triaryl-1,4-diamine-based polysquaraines: effect of co-solvent and monomer insertion on optoelectronic properties." Polymer Chemistry 9, no. 11: 1288-1292.
Front Cover: PCDTBT:PC71BM composite particles are prepared in water via a post-polymerization process: the nanoprecipitation. The particle size could be tuned by playing with various parameters and were integrated in the active layer on an organic photovoltaic cell by spray-coating. Further details can be found in article number 1700504 by Eric Cloutet and co-workers.
Geoffrey Prunet; Laurie Parrenin; Eleni Pavlopoulou; Gilles Pécastaings; Cyril Brochon; Georges Hadziioannou; Eric Cloutet. Macromol. Rapid Commun. 2/2018. Macromolecular Rapid Communications 2018, 39, 1 .
AMA StyleGeoffrey Prunet, Laurie Parrenin, Eleni Pavlopoulou, Gilles Pécastaings, Cyril Brochon, Georges Hadziioannou, Eric Cloutet. Macromol. Rapid Commun. 2/2018. Macromolecular Rapid Communications. 2018; 39 (2):1.
Chicago/Turabian StyleGeoffrey Prunet; Laurie Parrenin; Eleni Pavlopoulou; Gilles Pécastaings; Cyril Brochon; Georges Hadziioannou; Eric Cloutet. 2018. "Macromol. Rapid Commun. 2/2018." Macromolecular Rapid Communications 39, no. 2: 1.
International audienceRoom temperature flexible heat harvesters based on conducting polymers are ideally suited to cover the energy demands of the modern nomadic society. The optimization of their thermoelectric efficiency is usually sought by tuning the oxidation levels of the conducting polymers, even if such methodology is detrimental to the Seebeck coefficient (S) as both the Seebeck coefficient and the electrical conductivity (σ) are antagonistically related to the carrier concentration. Here we report a concurrent increase of S and σ and we experimentally derive the dependence of Seebeck coefficient on charge carrier mobility for the first time in organic electronics. Through specific control of the conducting polymer synthesis, we enabled the formation of a denser percolation network that facilitated the charge transport and the thermodiffusion of the charge carriers inside the conducting polymer layer, while the material shifted from a Fermi glass towards a semi-metal, as its crystallinity increased. This work sheds light upon the origin of the thermoelectric properties of conducting polymers, but also underlines the importance of enhanced charge carrier mobility for the design of efficient thermoelectric polymers
Ioannis Petsagkourakis; Eleni Pavlopoulou; Eric Cloutet; Yan Fang Chen; Xianjie Liu; Mats Fahlman; Magnus Berggren; Xavier Crispin; Stefan Dilhaire; Guillaume Fleury; Georges Hadziioannou. Correlating the Seebeck coefficient of thermoelectric polymer thin films to their charge transport mechanism. Organic Electronics 2018, 52, 335 -341.
AMA StyleIoannis Petsagkourakis, Eleni Pavlopoulou, Eric Cloutet, Yan Fang Chen, Xianjie Liu, Mats Fahlman, Magnus Berggren, Xavier Crispin, Stefan Dilhaire, Guillaume Fleury, Georges Hadziioannou. Correlating the Seebeck coefficient of thermoelectric polymer thin films to their charge transport mechanism. Organic Electronics. 2018; 52 ():335-341.
Chicago/Turabian StyleIoannis Petsagkourakis; Eleni Pavlopoulou; Eric Cloutet; Yan Fang Chen; Xianjie Liu; Mats Fahlman; Magnus Berggren; Xavier Crispin; Stefan Dilhaire; Guillaume Fleury; Georges Hadziioannou. 2018. "Correlating the Seebeck coefficient of thermoelectric polymer thin films to their charge transport mechanism." Organic Electronics 52, no. : 335-341.
The fabrication of organic solar cells from aqueous dispersions of photoactive nanoparticles has recently attracted the interest of the photovoltaic community, since these dispersions offer an eco-friendly solution for the fabrication of solar cells, avoiding the use of toxic solvents. In this work, aqueous dispersions of pure poly[n-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT) and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) nanoparticles, as well as of composite PC71BM:PCDTBT nanoparticles, are prepared using the nanoprecipitation postpolymerization method. These dispersions are subsequently used to form the active layer of organic photovoltaic cells. Thin films of PC71BM and PCDTBT are obtained by spray deposition of the nanoparticles' dispersions, and are characterized using a combination of spectroscopic and microscopic techniques. Photovoltaics that incorporate these active layers are fabricated thereafter. The impact of the annealing temperature and of the composition of the active layer on the efficiency of the solar cells is studied.
Geoffrey Prunet; Laurie Parrenin; Eleni Pavlopoulou; Gilles Pecastaings; Cyril Brochon; Georges Hadziioannou; Eric Cloutet. Aqueous PCDTBT:PC71 BM Photovoltaic Inks Made by Nanoprecipitation. Macromolecular Rapid Communications 2017, 39, 1 .
AMA StyleGeoffrey Prunet, Laurie Parrenin, Eleni Pavlopoulou, Gilles Pecastaings, Cyril Brochon, Georges Hadziioannou, Eric Cloutet. Aqueous PCDTBT:PC71 BM Photovoltaic Inks Made by Nanoprecipitation. Macromolecular Rapid Communications. 2017; 39 (2):1.
Chicago/Turabian StyleGeoffrey Prunet; Laurie Parrenin; Eleni Pavlopoulou; Gilles Pecastaings; Cyril Brochon; Georges Hadziioannou; Eric Cloutet. 2017. "Aqueous PCDTBT:PC71 BM Photovoltaic Inks Made by Nanoprecipitation." Macromolecular Rapid Communications 39, no. 2: 1.
The morphology of a novel promising material for green energy applications was described by combining two powerful techniques: GIWAXS and MD simulations.
Juan Felipe Franco-Gonzalez; Eleni Pavlopoulou; Eleni Stavrinidou; Roger Gabrielsson; Daniel T. Simon; Magnus Berggren; Igor V. Zozoulenko. Morphology of a self-doped conducting oligomer for green energy applications. Nanoscale 2017, 9, 13717 -13724.
AMA StyleJuan Felipe Franco-Gonzalez, Eleni Pavlopoulou, Eleni Stavrinidou, Roger Gabrielsson, Daniel T. Simon, Magnus Berggren, Igor V. Zozoulenko. Morphology of a self-doped conducting oligomer for green energy applications. Nanoscale. 2017; 9 (36):13717-13724.
Chicago/Turabian StyleJuan Felipe Franco-Gonzalez; Eleni Pavlopoulou; Eleni Stavrinidou; Roger Gabrielsson; Daniel T. Simon; Magnus Berggren; Igor V. Zozoulenko. 2017. "Morphology of a self-doped conducting oligomer for green energy applications." Nanoscale 9, no. 36: 13717-13724.
International audienceA series of carbazole-based polyazomethines have been synthesized under micro-wave irradiation and without transition-metal based catalyst. The impact of both the catenation brought by the carbazole subunits and the insertion of a co-monomer, i.e. 3,4 ethylene dioxythiophene (EDOT), on the optical and electrochemical properties have been studied. Among the different polyazomethines synthesized, the best in terms of optical and electrochemical properties has been found to be the one with the azomethine function linked in positions 2,7 of carbazole subunits. Upon the insertion of the EDOT comonomer, an increase of the molecular weight and a red-shift in the absorption spectra has been observed, corresponding to a diminution of the electronic gap
G. Garbay; L. Muccioli; E. Pavlopoulou; A. Hanifa; G. Hadziioannou; C. Brochon; E. Cloutet. Carbazole-based π-conjugated polyazomethines: Effects of catenation and comonomer insertion on optoelectronic features. Polymer 2017, 119, 274 -284.
AMA StyleG. Garbay, L. Muccioli, E. Pavlopoulou, A. Hanifa, G. Hadziioannou, C. Brochon, E. Cloutet. Carbazole-based π-conjugated polyazomethines: Effects of catenation and comonomer insertion on optoelectronic features. Polymer. 2017; 119 ():274-284.
Chicago/Turabian StyleG. Garbay; L. Muccioli; E. Pavlopoulou; A. Hanifa; G. Hadziioannou; C. Brochon; E. Cloutet. 2017. "Carbazole-based π-conjugated polyazomethines: Effects of catenation and comonomer insertion on optoelectronic features." Polymer 119, no. : 274-284.
By using different polysaccharide and polysulfonylimide type polyelectrolytes for the synthesis of aqueous PEDOT:polyelectrolyte dispersions, the influence of the polyelectrolyte backbone and of the anionic groups on the properties of the resulting PEDOT:polyelectrolyte complex has been studied. The obtained PEDOT:polyelectrolyte systems were characterized regarding the doping and the morphology of the complexes in dispersion as well as regarding the optoelectronic properties and the morphology of the dry PEDOT:polyelectrolyte films. Polyelectrolytes with high molar mass, a rigid backbone, and strongly acidic functionalities resulted in highly conducting PEDOT:polyelectrolyte films, while polyelectrolytes with flexible backbones and weakly acidic groups resulted in insulating PEDOT:polyelectrolyte systems. These findings could help to develop a palette of new PEDOT:polyelectrolyte systems, which correspond better to the specific requirements of different applications.
Anna Hofmann; Dimitrios Katsigiannopoulos; Muhammad Mumtaz; Ioannis Petsagkourakis; Gilles Pecastaings; Guillaume Fleury; Christophe Schatz; Eleni Pavlopoulou; Cyril Brochon; Georges Hadziioannou; Eric Cloutet. How To Choose Polyelectrolytes for Aqueous Dispersions of Conducting PEDOT Complexes. Macromolecules 2017, 50, 1959 -1969.
AMA StyleAnna Hofmann, Dimitrios Katsigiannopoulos, Muhammad Mumtaz, Ioannis Petsagkourakis, Gilles Pecastaings, Guillaume Fleury, Christophe Schatz, Eleni Pavlopoulou, Cyril Brochon, Georges Hadziioannou, Eric Cloutet. How To Choose Polyelectrolytes for Aqueous Dispersions of Conducting PEDOT Complexes. Macromolecules. 2017; 50 (5):1959-1969.
Chicago/Turabian StyleAnna Hofmann; Dimitrios Katsigiannopoulos; Muhammad Mumtaz; Ioannis Petsagkourakis; Gilles Pecastaings; Guillaume Fleury; Christophe Schatz; Eleni Pavlopoulou; Cyril Brochon; Georges Hadziioannou; Eric Cloutet. 2017. "How To Choose Polyelectrolytes for Aqueous Dispersions of Conducting PEDOT Complexes." Macromolecules 50, no. 5: 1959-1969.
International audienceA major issue that inhibits large-scale fabrication of organic solar modules is the use of chlorinated solvents considered as toxic and hazardous. In this work, composite particles of poly[N-9’-heptadecanyl-2,7-carbazole-alt-5,5-(4,7-di-2-thienyl-2’,1’,3’-benzothiadiazole] (PCDTBT) and [6,6]-Phenyl C71 butyric acid methyl ester (PC71BM) were obtained in water from a versatile and a ready-to-market methodology based on post-polymerization miniemulsification. Depending on experimental conditions, size-controlled particles comprising both the electron-donor and the electron-acceptor were obtained and characterized using transmission electron microscopy (TEM), atomic force microscopic (AFM), small-angle neutron scattering (SANS), UV-visible absorption and fluorescence spectroscopies. Intimate mixing of the two components was definitely asserted through PCDTBT fluorescence quenching in the composite nanoparticles. The water-based inks were used for the preparation of photovoltaic active layers which were subsequently integrated in organic solar cells
Laurie Parrenin; Gildas Laurans; Eleni Pavlopoulou; Guillaume Fleury; Gilles Pecastaings; Cyril Brochon; Laurence Vignau; Georges Hadziioannou; Eric Cloutet. Photoactive Donor–Acceptor Composite Nanoparticles Dispersed in Water. Langmuir 2017, 33, 1507 -1515.
AMA StyleLaurie Parrenin, Gildas Laurans, Eleni Pavlopoulou, Guillaume Fleury, Gilles Pecastaings, Cyril Brochon, Laurence Vignau, Georges Hadziioannou, Eric Cloutet. Photoactive Donor–Acceptor Composite Nanoparticles Dispersed in Water. Langmuir. 2017; 33 (6):1507-1515.
Chicago/Turabian StyleLaurie Parrenin; Gildas Laurans; Eleni Pavlopoulou; Guillaume Fleury; Gilles Pecastaings; Cyril Brochon; Laurence Vignau; Georges Hadziioannou; Eric Cloutet. 2017. "Photoactive Donor–Acceptor Composite Nanoparticles Dispersed in Water." Langmuir 33, no. 6: 1507-1515.