Search

We set out to demonstrate the development of a highly conductive polymer based on poly-(3,4-ethylenedithia thiophene) (PEDTT), PEDOTs structural analogue historically notorious for structural disorder and limited conductivities. The caveat therein was previously described to lie in intra-molecular repulsions. We demonstrate how a tremendous >2600-fold improvement in conductivity and metallic features, such as magnetoconductivity can be achieved. This is achieved through a careful choice of the counter-ion (sulphate) and the use of oxidative chemical vapour deposition (oCVD). It is shown that high structural order on the molecular level was established and the formation of crystallites tens of nanometres in size was achieved. We infer that the sulphate ions therein intercalate between the polymer chains, thus forming densely packed crystals of planar molecules with extended π-systems. Consequently, room-temperature conductivities of above 1000 S cm−1 are achieved, challenging those of conventional PEDOT:PSS. The material is in the critical regime of the metal–insulator transition., GRAPHICAL ABSTRACTS

In the search for alternatives to lithium batteries, aluminium makes a promising negative electrode due to its high theoretical specific energy and energy density. One battery chemistry making use of an aluminium negative electrode is the aluminium–poly(3,4-ethylenedioxythiophene) (PEDOT) battery, which has been shown to have long cycle life and specific energy comparable to other aluminium rechargeable batteries. The battery stores AlCl4− anions in the PEDOT cathode when charged. However, the storage mechanism is not well understood. Here, ab initio molecular dynamics simulations (AIMD) are used to help understand the optimum (relaxed) configuration of AlCl4− anions when stored on a single chain of PEDOT. Two main conclusions arise. Firstly, it is generally not stable to have two anions adsorbed to one monomer unit, and this configuration can be avoided for future work. Secondly, AIMD does not find lower energy configurations for the PEDOT/AlCl4− system than DFT geometry relaxation, providing that the starting geometry does not have two anions on the same monomer unit. Based on our results, we believe it is likely that similar behaviour will be observed in other conducting polymer systems.

[EN] The characteristics and electromechanical properties of conductive polymers together to their biocompatibility have boosted their application as a suitable tool in regenerative medicine and tissue engineering. However, conducting polymers as drug release materials are far from being ideal. A possibility to overcome this drawback is to combine conducting polymers with on-command delivery particles with inherent high-loading capacity. In this scenario, we report here the preparation of conduction polymers containing gated mesoporous silica nanoparticles (MSN) loaded with a cargo that is delivered on command by electro-chemical stimuli increasing the potential use of conducting polymers as controlled delivery systems. MSNs are loaded with Rhodamine B (Rh B), anchored to the conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) doped with poly[(4-styrenesulfonic acid)-co-(maleic acid)], functionalized with a bipyridinium derivative and pores are capped with heparin (P3) by electrostatic interactions. P3 releases the entrapped cargo after the application of ¿640 mV voltage versus the saturated calomel electrode (SCE). Pore opening in the nanoparticles and dye delivery is ascribed to both (i) the reduction of the grafted bipyridinium derivative and (ii) the polarization of the conducting polymer electrode to negative potentials that induce detachment of positively charged heparin from the surface of the nanoparticles. Biocompatibility and cargo release studies were carried out in HeLa cells cultures., Alba Garcia-Fernandez, Beatriz Lozano-Torres contributed equally to this work. A. Garcia-Fernandez and B. Lozano-Torres are grateful to the "Ministerio de Economia y Competitividad" of the Spanish Government for her PhD fellowships. J. F. Blandez thanks the "Universitat Politecnica de Valencia" for his postdoctoral fellowship (PAID-10-17). The authors thank to the Spanish Government (Projects RTI2018-100910-B-C41 and RTI2018-101599-B-C22 (MCUI/AEI/FEDER, EU)) and the Generalitat Valencia (Project PROMETEO2018-024) for support.

Composites of magnetic CoFe2O4 nanoparticles (MNP) in a poly(3,4-ethylenedioxythiophene) matrix at different ratios have been synthesized. Composites were characterized by electron microscopy, X-ray diffraction, thermal analysis, electrical conductivity, magnetization, and magnetoresistance studies. In the composites the MNP appear clustered, with an interparticle distance essentially constant, but where two regimes are distinguished for cluster separation: for high MNP concentrations an intercluster separation similar to the interparticle distance is found, while for low MNP contents the distance between clusters is larger than the interparticle separation. The electrical conductivity increases with polymer content, but being always far lower than general effective medium theory expectations. This indicates that the effect of MNP effect on polymer conduction is probably related to the generation of mechanical stress both by introducing additional scattering centers and by producing different arrangement of the polymer chains, compared with the pure PEDOT. The magnetization studies reveal the existence of the RKKY interaction, which couples ferromagnetically the MNP located in a cluster, while the dipolar interaction dominates the interaction between clusters. Magnetoresistance was studied for these composites, with a maximum value close to 0.7% at 0.7 T for the lowest polymer content. The magnetoresistance correlates very well with the reversible part of the magnetization, indicating that its possible origin should be associated with polymer mechanical deformation due to the magnetic-field-induced rotation of the MNP. Fil: Lanús Mendez Elizalde, Matías. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Acha, Carlos Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina Fil: Molina, Fernando Víctor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Antonel, Paula Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina

Organic semiconductors are constantly gaining interest in regenerative medicine. Their tunable physico-chemical properties, including electrical conductivity, are very promising for the control of stem-cell differentiation. However, their use for combined material-based and electrical stimulation remains largely underexplored. Therefore, we carried out a study on whether a platform based on the conductive polymer poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) can be beneficial to the differentiation of mouse embryonic stem cells (mESCs). The platform was prepared using the layout of a standard 24-well cell-culture plate. Polyethylene naphthalate foil served as the substrate for the preparation of interdigitated gold electrodes by physical vapor deposition. The PEDOT:PSS pattern was fabricated by precise screen printing over the gold electrodes. The PEDOT:PSS platform was able to produce higher electrical current with the pulsed-direct-current (DC) electrostimulation mode (1 Hz, 200 mV/mm, 100 ms pulse duration) compared to plain gold electrodes. There was a dominant capacitive component. In proof-of-concept experiments, mESCs were able to respond to such electrostimulation by membrane depolarization and elevation of cytosolic calcium. Further, the PEDOT:PSS platform was able to upregulate cardiomyogenesis and potentially inhibit early neurogenesis per se with minor contribution of electrostimulation. Hence, the present work highlights the large potential of PEDOT:PSS in regenerative medicine.

The electrochemical synthesis of poly(3,4-ethylenedioxythiophene) (PEDOT) was first carried out in the presence of mixtures of flexible-chain and rigid-chain polyacids and their Na-salts. Earlier on with the example of polyaniline, we have shown the non-additive effect of the rigid-chain component of polyacid mixtures on the electrodeposition of polyaniline films, their morphology and spectroelectrochemical properties. In this study, we confirmed the non-additive effect and showed that such mixed PEDOT–polyelectrolyte films possess unique morphology, spectroelectrochemical and ammonia sensing properties. The electrosynthesis was carried out in potential cycling, galvanostatic and potentiostatic regimes and monitored by in situ UV–Vis spectroscopy. UV–Vis spectroelectrochemistry of the obtained PEDOT–polyelectrolyte films revealed the dominating influence of the rigid-chain polyacid on the electronic structure of the mixed complexes. The mixed PEDOT–polyacid films demonstrated the best ammonia sensing performance (in the range of 5 to 25 ppm) as compared to the films of individual PEDOT–polyelectrolyte films.

Thin films of conducting polymer complexes with polysulfonic acids of various structures were electrochemically deposited onto transparent FTO electrodes. The behavior of the polymer-based optical ammonia vapor sensors in response to various concentrations of ammonia vapors, ranging from 5 to 135 ppm, was investigated, including the response time and response amplitude. It was found that the nature of the conducting polymers (poly (3,4-ethylenedioxythiophene), polypyrrole, polyaniline), as well as the structure of the polyacids, affected the sensing performance of the obtained complexes.

Organic bioelectronics involves the connection of organic semiconductors with living organisms, organs, tissues, cells, membranes, proteins, and even small molecules. In recent years, this field has received great interest due to the development of all kinds of devices architectures, enabling the detection of several relevant biomarkers, the stimulation and sensing of cells and tissues, and the recording of electrophysiological signals, among others. In this review, we discuss recent functionalization approaches for PEDOT and PEDOT:PSS films with the aim of integrating biomolecules for the fabrication of bioelectronics platforms. As the choice of the strategy is determined by the conducting polymer synthesis method, initially PEDOT and PEDOT:PSS films preparation methods are presented. Later, a wide variety of PEDOT functionalization approaches are discussed, together with bioconjugation techniques to develop efficient organic-biological interfaces. Finally, and by making use of these approaches, the fabrication of different platforms towards organic bioelectronics devices is reviewed.

Conductive poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is widely used for practical applications such as energy conversion and storage devices owing to its good flexibility, processability, high electrical conductivity, and superior optical transparency, among others. However, its hygroscopic character, short durability, and poor thermoelectric performance compared to inorganic counterparts has greatly limited its high-tech applications. In this work, PEDOT:PSS/SnO2 nanocomposites have been prepared via a simple, low cost, environmentally friendly method without the use of organic solvents or compatibilizing agents. Their morphology, thermal, thermoelectrical, optical, and mechanical properties have been characterized. Electron microscopy analysis revealed a uniform dispersion of the SnO2 nanoparticles, and the Raman spectra revealed the existence of very strong SnO2-PEDOT:PSS interactions. The stiffness and strength of the matrix gradually increased with increasing SnO2 content, up to 120% and 65%, respectively. Moreover, the nanocomposites showed superior thermal stability (as far as 70 degrees C), improved electrical conductivity (up to 140%), and higher Seebeck coefficient (about 80% increase) than neat PEDOT:PSS. On the other hand, hardly any change in optical transparency was observed. These sustainable nanocomposites show considerably improved performance compared to commercial PEDOT:PSS, and can be highly useful for applications in energy storage, flexible electronics, thermoelectric devices, and related fields., Comunidad de Madrid

Electrochemically synthesized poly(3,4,-ethylenedioxythiophene) (PEDOT) films obtained in the presence of eight different polysulfonate dopants are comparatively studied by means of electrochemical quartz crystal microbalance (EQCM) and X-ray Photoelectron Spectroscopy (XPS). Differences with respect to oxidation and doping levels (OL and DL), polymerization efficiency and redox behavior are revealed based on the interplay of three factors: the type of the dopant (acid or salt form), flexibility of the polysulfonate chains and molecular weight of the polysulfonate species. For the rigid- and semi-rigid-chain dopants, use of the salt form results in higher OL and DL values and substantial involvement of solvent molecules in the course of polymerization and redox transitions whereas in the presence of their acid form compact PEDOT films with minor ionic-solvent fluxes upon redox transitions are formed. In contrast, use of the salt form of the flexible chain polysulfonates results in PEDOT with lower OL and DL in comparison to the corresponding acid form. Significant effects are observed when comparing flexible chain dopants with different molecular weights. From a practical point of view the present investigations demonstrate the large scope of possibilities to influence some basic properties of PEDOT (Ol and DL, intensity and type of the ionic and solvent fluxes upon redox transition) depending on the used polysulfonate dopants.

Potassium-ion batteries (KIBs) have come up as a potential alternative to lithium-ion batteries due to abundant potassium storage in the crust. Red phosphorus is a promising anode material for KIBs with abundant resources and high theoretical capacity. Nevertheless, large volume expansion, low electronic conductivity, and limited K+ charging speed in red phosphorus upon cycling have severely hindered the development of red phosphorus-based anodes. To obtain improved conductivity and structural stability, surface engineering of red phosphorus is required. Poly(3,4-ethylenedioxythiophene) (PEDOT)-coated red phosphorus nanospheres (RPNP@PEDOT) with an average diameter of 60 nm were synthesized via a facile solution-phase approach. PEDOT can relieve the volume change of red phosphorus and promote electron/ion transportation during charge−discharge cycles, which is partially corroborated by our DFT calculations. A specific capacity of 402 mAh g−1 at 0.1 A g−1 after 40 cycles, and a specific capacity of 302 mAh g−1 at 0.5 A g−1 after 275 cycles, were achieved by RPNP@PEDOT anode with a high pseudocapacitive contribution of 62%. The surface–interface engineering for the organic–inorganic composite of RPNP@PEDOT provides a novel perspective for broad applications of red phosphorus-based KIBs in fast charging occasions.

International audience; An amperometric biosensor of high enzymatic response to the sensitive and selective detection of superoxide (2 .−) was designed utilizing a drop-coating approach for immobilizing the enzyme superoxide dismutase on Pt electrode modified with a thin layer of poly (3,4-ethylenedioxythiophene) (PEDOT). The PEDOT electrodeposited layer on Pt was characterized by cyclic voltammetry and atomic force microscopy (AFM). Then, drop-coating procedure was chosen for the immobilization of superoxide dismutase, which is incorporated at the electrode surface using a solution containing SOD, glutaraldehyde and bovine serum albumin (optimization composition : SOD 0.1%-ASB 2%-GA 2.5%.) This simple procedure allows forming a reproducible enzymatic biocomposite layer that allows optimal sensitivity and limit of detection for 2 .−. The synergistic effect integrates an effective conductivity and permoselectivity attributed to the PEDOT, as well as the specificity and selectivity of SOD for the detection of superoxide. A high sensitivity (0.82 ± 0.01 μA / μM) and a low detection limit of 11 nM for 2 .− were obtained, as well as good selectivity against main interfering biological compounds such as uric acid and ascorbic acid. Our results suggest that the biosensor could be used for the detection and quantification of 2 .− in vitro and in vivo.

The relation of molecular structures, morphologies, and thermoelectric (TE) properties of the poly(3,4-ethylenedioxythiophene): poly (styrene sulfonate)/polyaniline (PEDOT: PSS/PANi) composite films have been carefully investigated. Various nanostructured PANi were synthesized firstly. Then PEDOT: PSS were employed to prepare PEDOT: PSS/PANi composite films. The morphological and structural characterization reveal that PANi nanoflakes with planar molecule structure possess the most ordered chain stacking, resulting good crystallinity and the highest TE properties in PEDOT: PSS/PANi-nanoflakes composite films. The power factor of PEDOT: PSS/PANi composite films increases as follows, PEDOT: PSS/PANi-hollow spheres

Dye-sensitized solar cells (DSSCs) emerged in the early 1990s as a promising alternative to the classic silicon-based solar cell due to their unique combination of low cost, ease of fabrication, color palette for building integration, and high efficiency in indoor applications. This review article describes the fabrication and the properties of poly (3,4-ethylenedioxythiophene) (PEDOT)-based catalytic counter electrodes (CEs) for DSSCs. In particular, the electrochemical reactivity PEDOT CEs used in conjunction with alternative redox mediators for DSSCs is outlined. Among alternative redox shuttles, cobalt and copper complexes, as well as totally organic thiolate/disulfide, have been considered. Finally, PEDOT can also be used as a hole conductor material in electrolyte-free solid-state dye-sensitized solar cells. This review clearly shows that the progress in DSSCs development is strongly linked to the introduction of PEDOT as a new counter electrode material.

Printable organic electrochromic materials are the key component of flexible low power and low weight displays and dynamic shading systems. A vast number of more or less well-performing materials is reported in the literature, but only a very limited number of them have been tested in an industrially-relevant environment so far. Upscaling requires simplicity of synthesis, overall sustainability, low cost and compatibility with simple and high throughput wet-chemical deposition techniques, such as slot-die coating or inkjet printing. In the present paper, an original process is described that enables the controlled oxidative polymerization of a water insoluble, functionalized 3,4-ethylene dioxythiophene (EDOT) derivative. This process leads to the formation of an ink that consists solely of active polymeric material (no dispersing agents) and has suitable rheological properties for use in roll-to-roll slot-die coating or ink-jet printing. The straightforward deposition, followed by a simple thermal treatment, directly yields stable and homogeneous thin films with state-of-the-art electrochromic performance.

Monitoring nitrate ions is essential in agriculture, food industry, health sector and aquatic ecosystem. We show that a conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), can be used for nitrate sensing through a process in which nitrate ion uptake leads to oxidation of PEDOT and change of its optical properties. In this study, a new platform is developed in which a single-mode fibre coated at the tip with PEDOT is used for nitrate sensing. A crucial step towards this goal is introduction of carbonate exposure to chemically reduced PEDOT to a baseline value. The proposed platform exhibits the change in optical behaviour of the PEDOT layer at the tip of the fibre as it undergoes chemical oxidation and reduction (redox). The change in optical properties due to redox switching varies with the intensity of light back reflected by the fibre coated with PEDOT. The proposed platform during oxidation demonstrates linear response for the uptake of nitrate ions in concentrations ranging between 0.2 and 40 parts per million (ppm), with a regression coefficient R2=0.97 and a detection limit of 6.7 ppm. The procedure for redox switching is repeatable as the back reflection light intensity reaches &plusmn, 1.5% of the initial value after reduction.

Thesis (PhD(Energy and Advanced Manufacturing))--University of South Australia, 2021. Includes bibliographical references (pages 132-165) To date, CPs have been used as a sensing layer mainly because of their ease in synthesis and sensitivity to anions. However, the chemistry behind the CP-based sensors has been unclear and this PhD project, studies the chemical interaction mechanism between the CPs and anions in water. Vapor phase polymerisation (VPP) electrochemically reduced PEDOT was exposed chemically to different range of anions at 1 mM concentration under ambient conditions. This study revealed the interaction mechanism of PEDOT under chemical exposure through chemical and structural characterisation. Following, VPP polypyrrole and poly(3,4-(2,2-dimethyl-propylenedioxy) thiophene) were studied in a similar manner to PEDOT and this research showed oxygenation mechanism. Finally, VPP PEDOT was electrochemically reduced and exposed to a nitrate/nitrite mixture in water and it showed a specific electrochemical response.

Genetic code expansion provides powerful strategies to improve the properties of protein-based materials. One novel application of this technique is to genetically incorporate an electroactive functional group into proteins, which can be subsequently polymerized into conductive polymers, enabling fabrication of various protein–conductive polymer hybrids that are widely applicable in bioelectronics. To this end, we developed a technique to incorporate an amino acid bearing 3,4-ethylenedioxythiophene (EDOT), the monomer precursor of a well-known conductive polymer PEDOT. In Chapter 1, we review the basics of protein-based materials and genetic code expansion technology. We also highlight some examples where genetic code expansion was used for the development of protein-based materials. Finally, we discuss applications of protein and peptide-based materials in bioelectronics. In Chapter 2, we describe our effort to incorporate an amino acid bearing EDOT group (EDOT-Ala) designed as an analogue of aromatic canonical amino acids. We synthesized EDOT-Ala in three steps of organic reaction, and evaluated the activity of known aminoacyl-tRNA synthetase (aaRS) variants for EDOT-Ala. In addition, we performed evolution of aaRS for EDOT-Ala using two different evolution techniques: cell viability- based approach and phage-assisted approach. Although the evolution experiment did not yield an aaRS variant that can incorporate EDOT-Ala, the results presented in this chapter provide valuable information for engineering of aaRS and incorporation of non-canonical amino acids (ncAA) with bulky functional groups. In Chapter 3, we describe the incorporation of another EDOT-functionalized amino acid (EDOT-Lys) designed as an analogue of a canonical amino acid pyrrolysine (Pyl). When we co-expressed a GFP reporter and a mutant pyrrolysyl-tRNA synthetase (PylRS) in E. coli in the presence of EDOT-Lys, the cells exhibited strong fluorescence as an indication of successful incorporation of EDOT-Lys into GFP. We further confirmed the incorporation using MALDI-TOF mass spectrometry. In Chapter 4, we describe the electropolymerization of a model protein XTEN that carries genetically incorporated EDOT-Lys (XTEN-E49am). We performed electropolymerization of XTEN-E49am in the presence of a self-doping EDOT monomer (EDOT-S) by cyclic voltammetry. The solution formed dark blue solids immediately after the potential cycles. The composition of the product was determined by FT-IR spectroscopy, suggesting that one protein is found per 12.5 monomer units of PEDOT. In addition, we investigated the effect of amino acids located adjacent to EDOT-Lys. Although the presence of cysteine (Cys), lysine (Lys), methionine (Met), arginine (Arg), and tryptophan (Trp) located adjacent to EDOT-Lys had an impact on the electropolymerization of model peptides, XTEN proteins carrying these adjacent residues (XTEN-E49am-G50Z; Z = Cys, Lys, Met, Arg, Trp) were electropolymerized with EDOT-S without noticeable effect from these adjacent residues, indicating that the EDOT-Lys residues in proteins undergo electropolymerization with EDOT-S in different chemical environments. In Chapter 5, we describe the oxidative chemical polymerization of XTEN proteins and model peptides. When XTEN-E49am was polymerized with EDOT-S by addition of ammonium persulfate (APS) and iron(III) chloride (FeCl3), the solution yielded dark blue solids. To evaluate the reactivity of the EDOT-Lys residue in the protein, we reacted the protein with an end-capped EDOT derivative (EDOT-cap). MALDI-TOF mass spectrometry revealed the appearance of new peaks corresponding to the addition of one or two EDOT-caps to the protein, suggesting that EDOT-Lys residue in the protein can react with EDOT derivatives. We also investigated the effect of adjacent amino acids using a series of model peptides. In polymerization using APS without FeCl3 catalyst, peptides carrying basic amino acids (His, Lys, Arg) adjacent to EDOT-Lys showed enhanced polymerization compared to the ones carrying neutral and acidic adjacent residues. All the tested peptides polymerized well when FeCl3 was added as a catalyst. The results presented in this chapter provide valuable insights into synthesis of protein–PEDOT conjugates via oxidative chemical polymerization.

In situ electrochemical synthesis of an organic-inorganic hybrid material composed of poly(3,4-ethylenedioxythiophene) (PEDOT) and nickel-based Keggin type polyoxometalate, K7[NiIIINiII(H2O)W11O39].15H2O(NiPOM), has been proposed here. The remarkable optical and electrical properties of the PEDOT and the unique redox properties of NiPOM have synergistically combined to make the hybrid structure highly desired multi-functional materials for a myriad of applications. The driving force for the formation of hybrid structure is thought to be electrostatic interactions between POM anions and cationic polaron/bipolaron structures that in the PEDOT. PEDOT/NiPOM based hybrid composite modified graphite electrode has been used for non-enzymatic glucose sensor platform as a sample of applications. Furthermore, PEDOT/NiPOM based sensor platform was successfully utilized for detection of glucose content with the lowest detection limit in real samples like honey and milk. These results suggest that PEDOT/NiPOM metal-organic hybrid composite could be utilized as multi-functional material for a myriad of applications. © 2021 Wiley-VCH GmbH

In photocatalysis, small organic molecules are converted into desired products using light responsive materials, electromagnetic radiation, and electron mediators. Substitution of low molecular weight reagents with redox active functional materials may increase the utility of photocatalysis beyond organic synthesis and environmental applications. Guided by the general principles of photocatalysis, we design hybrid nanocomposites composed of n‐type semiconducting potassium poly(heptazine imide) (K‐PHI), and p‐type conducting poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) as the redox active substrate. Electrical conductivity of the hybrid nanocomposite, possessing optimal K‐PHI content, is reversibly modulated combining a series of external stimuli ranging from visible light under inert conditions and to dark conditions under an O2 atmosphere. Using a conductive polymer as the redox active substrate allows study of the photocatalytic processes mediated by semiconducting photocatalysts through electrical conductivity measurements., A conductive polymer (PEDOT:PSS) and potassium poly(heptazine imide) (K‐PHI) are combined in one hybrid nanocomposite as electron donor and photocatalyst, respectively. The composite represents an example of unconventional photocatalysis: K‐PHI modulates the physicochemical properties of the conductive polymer upon exposure to light and dark in different environments.

Conducting polymers are an interesting class of materials that can be tuned to have a range of properties through counterion doping. For most conducting polymers, the insertion of anions (the doping process) leads to the formation of carbocations (positive charge carriers) along the conjugated polymer backbone. In this research, we report on a scenario that arises where certain (commonly used) anions in water induce oxygenation of the conducting polymers heteroatom. This is in contrast to the widely reported doping process, and the recently reported hydrolysis of conducting polymers. We observe that the transition between these different conducting polymer-interactions/reactions is well described by the concept of structure-making and structure-breaking anions. Poly(3,4-propylenedioxy thiophene dimethyl) (PProDOT-Me2), polypyrrole (PPy), and poly(3,4-ethylenedioxy thiophene) (PEDOT) thin films are exposed to a range of anions in water. Both PProDOT-Me2 and PPy are susceptible to oxygenation, while in contrast PEDOT is doped, when exposed to structure-breaking anions. All the polymers show hydrolysis for structure-making anions. The knowledge of the interaction and/or reaction of conducting polymers with anions in water is not only critical to their application in devices for aqueous environments (i.e., sensing), but also for their processing and fabrication using water. Refereed/Peer-reviewed

Carbon nanomaterials (CNMs) and conjugated polymers (CPs) are actively investigated in applications such as optics, catalysis, solar cells, and tissue engineering. Generally, CNMs are implemented in devices where the relationship between the active elements and the micro and nanostructure has a crucial role. However, they present some limitations related to solubility, processibility and release or degradability that affect their manufacturing. CPs, such as poly(3,4-ethylenedioxythiophene) (PEDOT) or derivatives can hide this limitation by electrodeposition onto an electrode. In this work we have explored two different CNMs immobilization methods in 2D and 3D structures. First, CNM/CP hybrid 2D films with enhanced electrochemical properties have been developed using bis-malonyl PEDOT and fullerene C60. The resulting 2D films nanoparticulate present novel electrochromic properties. Secondly, 3D porous self-standing scaffolds were prepared, containing carbon nanotubes and PEDOT by using the same bis-EDOT co-monomer, which show porosity and topography dependence on the composition. This article shows the validity of electropolymerization to obtain 2D and 3D materials including different carbon nanomaterials and conductive polymers. This research was funded by the Spanish Ministry of Economy and Competitiveness MINECO (project CTQ2016-76721-R), the University of Trieste, Diputación Foral de Gipuzkoa program Red (101/16), the European Commission (H2020-MSCA-RISE-2016, grant agreement no. 734381, acronym CARBO-IMmap) and ELKARTEK bmG2017 (ref: Elkartek KK-2017/00008, BOPV resolution: 8 Feb 2018). M.P., as the recipient of the AXA Chair, is grateful to the AXA Research Fund for financial support. This work was performed under the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency Grant no. MDM-2017-0720. N.A. has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 753293, acronym NanoBEAT.

peer-reviewed Biodegradable strain sensors able to undergo controlled degradation following implantation have recently received significant interest as novel approaches to detect pathological tissue swelling or non-physiological stresses. In this study, the physicomechanical, electrochemical and active pressure sensing behavior of an electrically conductive and biodegradable poly(glycerol sebacate urethane) (PGSU) composite, reinforced with poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) functionalized carbon nanotubes (CNTs), was evaluated in vitro. Analysis of these PGSU-CNTs composites demonstrated that the incorporation of functionalized CNTs into a biodegradable elastomer resulted in enhanced mechanical strength, conductivity and tailored matrix biodegradation. PGSU-CNT composites were subsequently formulated into flexible and active pressure sensors which demonstrated optimal sensitivity to applied 1% uniaxial tensile strains. Finally, cytocompatibility analysis a with primary neural culture confirmed that PGSU-CNT composites exhibited low cytotoxicity, and supported neuron adhesion, viability, and proliferation in vitro.

We demonstrate a water-based synthetic route to fabricate composite inverse opals for simultaneous detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA). Our process involves the conformal deposition of poly(3,4-ethylenedioxythiophene) (PEDOT) and PEDOT/Au on the skeletons of Ni inverse opals via cyclic voltammetric scans (CV) to initiate the electropolymerization of 3,4-ethylenedioxythiophene (EDOT) monomers. The resulting samples, Ni@PEDOT, and Ni@PEDOT/Au inverse opals, exhibit a three-dimensional ordered macroporous platform with a large surface area and interconnected pore channels, desirable attributes for facile mass transfer and strong reaction for analytes. Structural characterization and material/chemical analysis including scanning electron microscope, X-ray photoelectron spectroscopy, and Raman spectroscopy are carried out. The sensing performances of Ni@PEDOT and Ni@PEDOT/Au inverse opals are explored by conducting CV scans with various concentrations of AA, DA, and UA. By leveraging the structural advantages of inverse opals and the selection of PEDOT/Au composite, the Ni@PEDOT/Au inverse opals reveal improved sensing performances over those of conventional PEDOT-based nanostructured sensors.

Thesis (Master)--Izmir Institute of Technology, Chemistry, Izmir, 2020, Includes bibliographical references (leaves: 34-40), Text in English; Abstract: Turkish and English, This study aims to produce polymer nanofiber / poly (3, 4 ethylene dioxythiophene) / metal particle hybrid composite as a bioelectronic interface for the detection of volatile organic compounds in human breath. The sensor platform consists of two layers: polymeric nanofiber structure and conductive layer. Polyurethane (PU), polycaprolactone (PCL) and poly L-lactide-co-ɛ-caprolactone (PLLCL) were selected to form polymeric nanofibers with electrospinning. For electrospinning process, solutions of polyurethane (PU) (25wt%) in DMF, polycaprolactone (PCL) (20wt%) in DCM (4) -DMF (1) and poly L-lactide-co-ɛ-caprolactone (PLLCL) (10wt%) in DCM (9) -DMF (1) are prepared. PU, PCL and PLLCL polymer solutions are subjected to 25 kV, 29kV and 25 kV electrical potential, respectively, to produce electrospinning fibers. Poly(3,4-ethylenedioxythiophene) (PEDOT) and multi-walled carbon nanotubes (MWCNTs) are used to produce conductive layers on PU, PCL and PLLCL polymer nanofibers. The produced sensor platforms are tested by the electrochemical station, which records the electrical current change over time. The sensing mechanism is assumed to be the adsorption of VOCs to the conductive PEDOT and CNT layer, thus blocking the electron current on the PEDOT and CNT network and causing resistance change. More clearly; swelling of the polymer structure in the sensor causes destruction in the upper layer and micro-dimensional cracks in the PEDOT and CNT network, increasing resistance to electron flow and decreasing current. Organic volatile compounds (acetone, toluene, ethanol, isopene etc.) are detected from ppm to ppb range and reproducible and reliable responses are recorded., Bu çalışma, insan nefesindeki uçucu organik bileşiklerin saptanması için bir biyoelektronik arayüz olarak polimer nanofiber / poli (3,4 etilen dioksitiofen) / metal parçacık hibrid kompozit üretmeyi amaçlamaktadır. Sensör platformu iki katmandan oluşur: polimerik nanofiber yapı ve iletken katman. Elektroeğirme metodu ile polimerik nanofiberler oluşturmak için poliüretan (PU), polikaprolakton (PCL) ve poli L-laktit-ko-p-kaprolakton (PLLCL) seçilmiştir. Elektroeğirme yöntemi için polimer çözeltileri şu şekilde hazırlanmıştır: PU (wt 25%) + DCM-DMF, PCL (wt 20%) + DCM-DMF ve PLLCL (wt 10%) + DCM-DMF. PU, PCL ve PLLCL polimer çözeltileri, elektrospun fiberler üretmek için sırasıyla 25 kV, 29kV ve 25 kV elektrik potansiyeline maruz bırakılır. Poli (3,4-etilendioksitiofen) (PEDOT) ve çok duvarlı karbon nanotüpler (MWCNT'ler), PU, PCL ve PLLCL polimer nanofiberleri üzerinde iletken katmanlar üretmek için kullanılır. Üretilen sensör platformları, zaman içindeki elektrik akımı değişimini kaydeden elektrokimyasal istasyon tarafından test edilir. Algılama mekanizmasının, VOC'lerin iletken PEDOT ve CNT katmanına adsorpsiyonu olduğu varsayılır, böylece PEDOT ve CNT ağı üzerindeki elektron akımını bloke eder ve direnç değişikliğine neden olur. Daha açık bir şekilde; sensördeki polimer yapısının şişmesi, PEDOT ve CNT ağında üst katman ve mikro boyutlu çatlaklara zarar vererek elektron akışına karşı direnci arttırır ve akımı azaltır. Organik uçucu bileşikler (aseton, toluen, etanol, izopen vb.) ppm ila ppb aralığında tespit edilir ve tekrarlanabilir ve güvenilir tepkiler kaydedilir.

We have successfully fabricated poly(3,4-ethylenedioxythiophene) (PEDOT) derivative nanohybrid coatings on flexible SUS316L stainless steel by electrochemical polymerization, which can offer anti-fouling and anti-bacterial capabilities. PEDOT derivative nanohybrids were prepared from polystyrene sulfonates (PSS) and graphene oxide (GO) incorporated into a conducting polymer of PEDOT. Additionally, the negative charge of the PEDOT/GO substrate was further modified by poly-diallyldimethylammonium chloride (PDDA) to form a positively charged surface. These PEDOT derivative nanohybrid coatings could provide a straightforward means of controlling the surface energy, roughness, and charges with the addition of various derivatives in the electrochemical polymerization and electrostatically absorbed process. The characteristics of the PEDOT derivative nanohybrid coatings were evaluated by Raman spectroscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), water contact angle, and surface potential (zeta potential). The results show that PEDOT/PSS and PEDOT/GO nanohybrid coatings exhibit excellent anti-fouling capability. Only 0.1% of bacteria can be adhered on the surface due to the lower surface roughness and negative charge surface by PEDOT/PSS and PEDOT/GO modification. Furthermore, the anti-bacterial capability (7 mm of inhibition zone) was observed after adding PDDA on the PEDOT/GO substrates, suggesting that the positive charge of the PEDOT/GO/PDDA substrate can effectively kill bacteria (Staphylococcus aureus). Given their anti-fouling and anti-bacterial capabilities, PEDOT derivative nanohybrid coatings have the potential to be applied to biomedical devices such as cardiovascular stents and surgical apparatus.

An overview of modern quantum chemical methods is presented followed by a discussion of their application in the field of conducting organic polymers (COPs), with a view towards modelling the cathodic half-cell of a poly(3,4-ethylenedioxythiophene) (PEDOT) cathode in an AlCl3-1-ethyl-3-methylimidazolium chloride (EMImCl) ionic liquid electrolyte. The most popular combination of hybrid DFT functional and polarized moderate basis set has been broadly and successfully applied to COPs in the literature. However, in the presence of anions and intermolecular interactions, diffuse functions and dispersion corrections must also be included. A comprehensive specification of these elements appears well suited to the determination of many relevant parameters including molecular geometry, bandgap of oligomers and energies for systems including multiple chains and chloroaluminate anions. However, range-separated hybrid functionals may be more suitable for determining electron transport properties of very long chains. The clearest benefit of DFT to this system is the ability to visualize charge distribution and the interaction between charged PEDOT and the active species, which will help to explain the specific capacity, voltage and charge/discharge characteristics — insights that may help identify further improvements.

International audience; An approach providing cation selective PEDOT:polyelectrolyte mixed conductors is presented in this communication, based on the structural modification of this ambivalent (ionic and electronic conductive) polymer complex. First, an 18-crown-6 moiety was integrated into the styrene sulfonate monomer structure as a specific metal cation scavenger particularly targeting K+ vs Na+ detection. This newly functionalized monomer has been characterized by 1H- NMR titration to evaluate the ion selectivity. Aqueous PEDOT dispersion inks containing the polymeric ion-selective moieties have been designed and their electrical and electrochemical properties have been analysed. These biocompatible inks are the first proof-of-concept step towards ion selectivity in view of their interfacing with biological cells and microorgans of interest in the field of biosensors and physiology.

Polyethylene dioxythiophene and polyethylene sulfonic acid (PEDOT/PSS) composite is gathering attention as an organic transparent conductive film material. However, it requires a core-shell structure in which conductive PEDOT is covered with insulating PSS. Providing film formability and a carrier to PEDOT, the PSS shell hinders carrier conduction as an insulating barrier. In this study, we realized that creating a macro-separated PEDOT/PSS composite by using a polyelectrolyte brush substrate and in-situ PEDOT polymerization without the PSS barrier increases durability and conductivity in comparison with commercially available PEDOT/PSS film, achieving a conductivity of 5000&ndash, 6000 S/cm.

Vapor deposition of tosylate-doped poly(3,4-ethylenedioxythiophene) (PEDOT) has been templated to create hollow nanosphere coatings on carbon paper electrodes. The electrochemistry of the PEDOT hollow nanosphere coatings were characterized in nonvolatile and nonflammable Li-based N-methyl-N-propyl pyrrolidinium bis(fluorosulfonyl)imide electrolytes. These electrodes exhibit high electrochemical activity for the given deposited mass owing to their heightened electrochemical active area. Furthermore, a multilayer of PEDOT hollow nanospheres as the cathode in a Li coin cell provides stability during repeated charge–discharge cycling against a Li–metal foil anode. With performance equivalent to the theoretical limit for PEDOT (140 mA h g–1), the Li|PEDOT cell has a significant specific energy of ∼340 W h/kg. These results give insights into the fabrication and use of nanostructured vapor-deposited conducting polymers for energy storage devices. usc Refereed/Peer-reviewed

Rapid Prototyping (RP) promises to induce a revolutionary impact on how the objects can be produced and used in industrial manufacturing as well as in everyday life. Over the time a standard technique as the 3D Stereolithography (SL) has become a fundamental technology for RP and Additive Manufacturing (AM), since it enables the fabrication of the 3D objects from a cost-effective photocurable resin. Efforts to obtain devices more complex than just a mere aesthetic simulacre, have been spent with uncertain results. The multidisciplinary nature of such manufacturing technique furtherly hinders the route to the fabrication of complex devices. A good knowledge of the bases of material science and engineering is required to deal with SL technological, characterization and testing aspects. In this framework, our study aims to reveal a new approach to obtain RP of complex devices, namely Organic Electro-Chemical Transistors (OECTs), by SL technique exploiting a resin composite based on the conductive poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) and the photo curable Poly(ethylene glycol) diacrylate (PEGDA). A comprehensive study is presented, starting from the optimization of composite resin and characterization of its electrochemical properties, up to the 3D OECTs printing and testing. Relevant performances in biosensing for dopamine (DA) detection using the 3D OECTs are reported and discussed too.

A green, efficient and stable solar cell based only on water and safe and cheap elements of the periodic table is proposed in this work, finally consolidating (also from a sustainability viewpoint) the concept of “artificial photosynthesis” studied for decades by the scientific community. The concept of dye-sensitized solar cells is re-proposed here with a metal-free organic dye, an iodine-based electrolyte in a 100% aqueous environment and a new cathode (cationic PEDOT) synthesized for the first time with the aim of inhibiting the repulsion between the anions of redox couples and the PEDOT:PSS matrix commonly used as the counter-electrode. This elegant setup leads to a record efficiency of 7.02%, the highest value ever obtained for a water-based solar cell and, in general, for a photovoltaic device free of both organic solvents and expensive/heavy metals., A new cationic PEDOT derivative inhibits repulsion phenomena within iodine-based electrolytes, boosting the efficiency of aqueous solar cells.

The water dispersion of the conductive polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) is one of the most used material precursors in organic electronics also thanks to its industrial production. There is a growing interest for conductive polymers that could be alternative surrogates or replace PEDOT:PSS in some applications. A recent study by our group compared electrodeposited PEDOT:Nafion vs PEDOT:PSS in the use for neural recordings. Here, we introduce an easy and reproducible synthetic protocol to prepare a water dispersion of PEDOT:Nafion. The conductivity of the pristine material is on the order of 2 S cm-1 and was improved up to ≈6 S cm-1 upon treatment with ethylene glycol. Faster ion transfer was assessed by electrochemical impedance spectroscopy (EIS), and, interestingly, an improved adhesion was observed for coatings of the new PEDOT:Nafion dispersion on glass substrates, even without the addition of the silane cross-linker needed for PEDOT:PSS. As proof of concept, we demonstrate the use of this novel water dispersion of PEDOT:Nafion in three different organic electronic device architectures, namely, an organic electrochemical transistor (OECT), a memristor, and an artificial synapse.