Conductive Polymer Research Articles

Redox Chemistry Mediated Control of Morphology and Properties in Electrically Conductive Coordination Polymers: Opportunities and Challenges

Redox Chemistry Mediated Control of Morphology and Properties in Electrically Conductive Coordination Polymers: Opportunities and Challenges

P-Toluenesulfonic Acid Modified Two-Dimensional ZrSe2 as a Hole Transport Layer for High-Performance Organic Solar Cells.

Two-dimensional (2D) materials have attracted attention due to their excellent optoelectronic properties, but their applications are limited by their defects and vacancies. Surface modification is an effective method to restore their performance. Here, ZrSe2 is modified with conductive polymer p-toluenesulfonic acid (PTSA). It is found that PTSA can obtain electrons of ZrSe2 through the combination of -SO3H and ZrSe2, thus forming interfacial dipoles, which improve the work function of ZrSe2. In addition, -OH in PTSA can effectively fill the Se vacancy in ZrSe2 to form P-type doping, thereby improving its conductivity. ZrSe2 modified by the PTSA material is first used as a hole transport layer (HTL) in organic solar cells (OSCs). The efficiency of OSCs based on the PBDB-T:ITIC and PM6:L8-BO binary active layer with ZrSe2:PTSA as the novel HTL reaches 10.66 and 18.14%, which are obviously higher than the efficiency of OSCs with pure ZrSe2 as the HTL (8.48 and 15.64%). More interestingly, the stability of the device with ZrSe2:PTSA as HTL is significantly better than that of PEDOT:PSS. This study shows that the modification of the organic material can effectively improve the photoelectric performance of ZrSe2 and explores the physical mechanism of the interaction between the organic modifier and 2D materials.

Inkjet printed acrylate-urethane modified poly(3,4-ethylenedioxythiophene) flexible conductive films

Abstract Flexible electronics is a new generation of electronic devices in which electronic components are integrated into flexible substrates. It is used in the fabrication of displays, solar cells, integrated circuits, and increasingly in the fabrication of electronic skin (E-skin), which can mimic the properties of human skin by being able to follow skin movements and flexures without loss of mechanical and electrical properties. E-skin is suitable for integrating various sensors to monitor personal health. Conductive polymers are used in flexible electronics due to their electrical conductivity, low mass, and stability. However, their main disadvantage is their brittleness, which is why they don’t possess flexibility property without modification. Therefore, in this work, the conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) was used as the main chain and the side branches of poly(acrylate-urethane) (PAU) were grafted onto it by atom transfer radical polymerization (ATRP) onto it, obtaining the grafted copolymer PEDOT-g-PAU. In this way, the main chain of PEDOT retains the property of electrical conductivity without losing conjugation, while the side branches of PAU have the ability to crosslink non-covalently through hydrogen bonds with PAU side branches of adjacent polymer molecules due to the presence of oxygen in their structure. The presence of hydrogen bonds allows increasing the stretchability and flexibility of the material, and they also have the ability to spontaneously renew themselves when they break due to excessive stress. Three different synthesis conditions were used to obtain polymers of different structure, which were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and measurement of electrical conductivity with a four-point probe (4PP) method. The obtained graft copolymer was prepared in the form of ink and printed on a polyurethane (PU) substrate using inkjet technique. The conductivity of the printed layer, its elongation and adhesion were investigated, while possible delamination of the printed polymer layer was also monitored. The results showed that the PEDOT-g-PAU copolymer was successfully synthesized and inkjet printing on PU film was successful. The obtained material has satisfactory electrical and mechanical properties and could be used for the integration of fully functional biosensors with further optimization of the composition.

An n‐Type Open‐Shell Conjugated Polymer with High‐Spin Ground‐State and High Intrinsic Electrical Conductivity

Open‐shell conjugated polymers with a high intrinsic conductivity and high‐spin ground state hold considerable promise for applications in organic electronics and spintronics. Herein, two novel acceptor‐acceptor (A‐A) conjugated polymers based on a highly electron‐deficient quinoidal benzodifurandione unit have been developed, namely DPP‐BFDO‐Th and DPP‐BFDO. The incorporation of the quinoidal moiety into the polymers backbones enables deeply aligned lower‐lying lowest unoccupied molecular orbital (LUMO) levels of below −4.0 eV. Notably, DPP‐BFDO exhibits an exceptionally low LUMO (−4.63 eV) and a high‐spin ground state characterized by strong diradical characters. Moreover, a self‐doping through intermolecular charge‐transfer is observed for DPP‐BFDO, as evidenced by X‐ray photoelectron spectroscopy (XPS) studies. The high carrier concentration in combination with a planar and linear conjugated backbone yields a remarkable electrical conductivity (σ) of 1.04 S cm−1 in the “undoped” native form, ranking among the highest values reported for n‐type radical‐based conjugated polymers. When employed as an n‐type thermoelectric material, DPP‐BFDO achieves a power factor of 12.59 μW m−1 K−2. Furthermore, upon n‐doping, the σ could be improved to 65.68 S cm‐1. This study underscores the great potential of electron‐deficient quinoidal units in constructing dopant‐free n‐type conductive polymers with a high‐spin ground state and exceptional intrinsic conductivity.

Optimizing Conductive Polymer Bulk Structure: Influence of Polymerization Temperature on Photocatalytic Performance for Sustainable Hydrogen Production

The influence of the polymerization temperature upon the bulk‐structure‐doped conductive polymer polyaniline (emeraldine‐salt, PANI) on the semiconducting, optical, and electrical properties of the photocatalyst is investigated. When the B‐PANI polymerization temperature increases from 5 to 60 °C, the crystallinity and conductivity of Pt/N‐TiO2/B‐PANI (PNT/B‐PANI) decreases. To rectify the problems of recycling convenience and secondary pollution, this study combines a photocatalyst and a porous polystyrene film for sustainable hydrogen production. The photocatalytic performance of the polystyrene/PNT/B‐PANI‐5 (PS/PNT/B‐PANI‐5) photocatalyst film (27 047 μmol h−1 g−1) under simulated sunlight irradiation is enhanced by a factor of up to 1.6 compared to that of PS/PNT. Therefore, the PS/PNT/B‐PANI photocatalyst film is a visible‐light photocatalyst which is a promising candidate for enhancing photocatalytic recycling convenience.

An n-Type Open-Shell Conjugated Polymer with High-Spin Ground-State and High Intrinsic Electrical Conductivity.

Open-shell conjugated polymers with a high intrinsic conductivity and high-spin ground state hold considerable promise for applications in organic electronics and spintronics. Herein, two novel acceptor-acceptor (A-A) conjugated polymers based on a highly electron-deficient quinoidal benzodifurandione unit have been developed, namely DPP-BFDO-Th and DPP-BFDO. The incorporation of the quinoidal moiety into the polymers backbones enables deeply aligned lower-lying lowest unoccupied molecular orbital (LUMO) levels of below -4.0 eV. Notably, DPP-BFDO exhibits an exceptionally low LUMO (-4.63 eV) and a high-spin ground state characterized by strong diradical characters. Moreover, a self-doping through intermolecular charge-transfer is observed for DPP-BFDO, as evidenced by X-ray photoelectron spectroscopy (XPS) studies. The high carrier concentration in combination with a planar and linear conjugated backbone yields a remarkable electrical conductivity (σ) of 1.04 S cm-1 in the "undoped" native form, ranking among the highest values reported for n-type radical-based conjugated polymers. When employed as an n-type thermoelectric material, DPP-BFDO achieves a power factor of 12.59 μW m-1 K-2. Furthermore, upon n-doping, the σ could be improved to 65.68 S cm-1. This study underscores the great potential of electron-deficient quinoidal units in constructing dopant-free n-type conductive polymers with a high-spin ground state and exceptional intrinsic conductivity.

First-principles prediction of one-dimensional conductive metallic organic polymers as ultrahigh energy density anode for lithium-ion batteries.

Metal-Organic Polymers (MOPs) have attracted growing attention for lithium-ion battery (LIB) applications due to their merits in orderly ionic transportation and robust structure stability in electrochemical reactions. However, they suffer from poor electronic conductivity. In this work, we apply first-principles density functional theory to explore the potential of three one-dimensional (1D) electrically conductive C6H2S4TM (TM = Fe, Co, and Ni) MOPs with the π-d conjugated coordination as anode materials for Li+ ions storage. Our theoretical results reveal that these 1D MOPs possess a superior theoretical capacity of over 748 mA h g-1. In particular, the 1D C6H2S4Ni MOP shows an exceptional theoretical specific capacity of 1110 mA h g-1 based on the three-electron transferring reaction, which significantly outperforms the traditional graphite-based anode material in LIBs. Moreover, the resonant charge transfer between Ni metal and ligand within the 1D C6H2S4Ni MOP reduces the diffusion energy barrier of the Li atoms when they migrate on the surface of the MOP. The ultrahigh theoretical specific capacity of the C6H2S4Ni MOP predicts that it can be a promising anode material for LIBs.

A Review of Conductivity of Conductive Polymers; Polyaniline (Pani) and its Nanocomposites

A Review of Conductivity of Conductive Polymers; Polyaniline (Pani) and its Nanocomposites

Effect of Aggregation Structure on Capacitive Energy Storage in Conducting Polymer Films.

Conducting polymers (CPs), a significant class of electrochemical capacitor electrode materials, exhibit exceptional capacitive energy storage performance in aqueous electrolytes. Current research primarily concentrates on enhancing the electrical conductivity and capacitive performance of CPs via molecular design and structural control. However, the absence of a comprehensive understanding of the impact of molecular chain spatial order on ion/electron transport and capacitive performance impedes the development and optimization of advanced electrode materials. Here, a solvent treatment strategy is employed to modulate the molecular chain spatial order of PEDOT:PSS films. The results of electrochemical performance tests and Grazing Incidence Wide Angle X-ray Scattering (GIWAXS) show that PEDOT:PSS films with both face-on and edge-on orientations exhibit exceptional electronic conductivity and ion diffusion efficiency, with capacitive performance 1.33 times higher than that of PEDOT:PSS films with only edge-on orientation. Consequently, molecular chain orientations conducive to charge transport not only enhance inter-chain coupling, but also effectively reduce ion transport resistance, enabling efficient capacitive energy storage. This research provides novel insights for the design and development of higher performance CPs-based electrode materials.

Electrochemical benefits of conductive polymers as a cathode material in LFP battery technology

Electrochemical benefits of conductive polymers as a cathode material in LFP battery technology

Synergistic Interface Platforms: Designing Superhydrophilic Conductive Nanoparticle‐Decorated Nanofibrous Membranes

AbstractIn today's technological landscape, advancing methods for producing conductive membranes that simplify and streamline the development of advanced interface materials is crucial. This study introduces a versatile and innovative method for fabricating superhydrophilic, conductive nanofibrous membranes based on the in situ synthesis of polypyrrole nanoparticles on poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) electrospun fibers. The composite membranes morphologically exhibit a particle‐decorated nanofibrous configuration, with polypyrrole nanoparticles distributed along the individual fibers' surface. The nanoparticle‐nanofiber configuration shows distinctive properties; electrochemically, the electrospun mats demonstrate excellent inherent electrical conductivity, good cyclic and high electrochemical stability, and low resistance. Furthermore, the amphiphilic and superhydrophilic behavior, achieved through nanotopography, porosity and interactions between the intrinsically conductive polymer and the PVDF‐HFP fibers, enables efficient uptake of polar and nonpolar analytes. The membranes also demonstrate good in vitro cell viability of both murine and human fibroblasts. Given its efficient interaction with liquids and omnidirectional 360‐degree conductivity, this material emerges as an excellent candidate for use as a biocompatible, multifunctional interface layer. The produced nanoparticle‐nanofibrous membrane materials offer a promising platform for interface applications, featuring enhanced spatiotemporal configurations and wide‐ranging applicability.

Application of Conductive Polymer in TiO2-Based UV Photodetectors: A Review

Application of Conductive Polymer in TiO₂-Based UV Photodetectors: A Review

Pyroresistive response of percolating conductive polymer composites

Pyroresistive response of percolating conductive polymer composites

Biocompatible PANI-Encapsulated Chemically Modified Nano-TiO2 Particles for Visible-Light Photocatalytic Applications.

Polyaniline (PANI) constitutes a very propitious conductive polymer utilized in several biomedical, as well as environmental applications, including tissue engineering, catalysis, and photocatalysis, due to its unique properties. In this study, nano-PANI/N-TiO2 and nano-PANI/Ag-TiO2 photocatalytic composites were fabricated via aniline's oxidative polymerization, while the Ag-and N-chemically modified TiO2 nanopowders were synthesized through the sol-gel approach. All produced materials were fully characterized. Through micro-Raman and FT-IR analysis, the co-existence of PANI and chemically modified TiO2 particles was confirmed, while via XRD analysis the composites' average crystallite size was determined as ≈20 nm. The semi-crystal structure of polyaniline exhibits higher photocatalytic efficiency compared to that of other less crystalline forms. The spherical-shaped developed materials are innovative, stable (zeta potential in the range from -26 to -37 mV), and cost-effective, characterized by enhanced photocatalytic efficiency under visible light (energy band gaps ≈ 2 eV), and synthesized with relatively simple methods, with the possibility of recycling and reusing them in potential future applications in industry, in wastewater treatment as well as in biomedicine. Thus, the PANI-encapsulated Ag and N chemically modified TiO2 nanocomposites exhibit high degradation efficiency towards Rhodamine B dye upon visible-light irradiation, presenting simultaneously high biocompatibility in different normal cell lines.

Biphasic nanocomposite films of polypyrrole and poly(3,4-ethylene dioxythiophene) using a surface-tethered dopant strategy

Using a newly invented surface-tethered dopant approach for the electrochemical polymerization growth of conductive polymer films, nanocomposites are created consisting of two distinct phases of polypyrrole (PPy) and Poly(3,4-ethylene dioxythiophene) (PEDOT). The growth of the conductive nanocomposite films takes advantage of the unique way in which a conductive polymer film forms when grown using a surface-tethered dopant, starting out as a highly nanoporous film that gradually becomes more and more solid as additional polymer deposition occurs preferentially within the nanopores rather than at the films outer surface. Nanocomposite films can thus be fabricated simply and controllably by first growing one nanoporous conductive polymer film followed by the deposition of a second conductive polymer within the nanopores of the first. This study investigates the morphological and electrochemical properties of nanocomposite films grown using a surface-tethered dopant and how these properties are affected by simple changes in electrochemical polymerization parameters.

Comprehensive Investigation of the Temperature-Dependent Electromechanical Behaviors of Carbon Nanotube/Polymer Composites.

The performances of flexible piezoresistive sensors based on polymer nanocomposites are significantly affected by the environmental temperature; therefore, comprehensively investigating the temperature-dependent electromechanical response behaviors of conductive polymer nanocomposites is crucial for developing high-precision flexible piezoresistive sensors in a wide-temperature range. Herein, carbon nanotube (CNT)/polydimethylsiloxane (PDMS) composites widely used for flexible piezoresistive sensors were prepared, and then the temperature-dependent electrical, mechanical, and electromechanical properties of the optimized CNT/PDMS composite in the temperature range from -150 to 150 °C were systematically investigated. At a low temperature of -150 °C, the CNT/PDMS composite becomes brittle with a compressive modulus of ∼1.2 MPa and loses its elasticity and reversible sensing capability. At a high temperature (above 90 °C), the CNT/PDMS composite softens, shows a fluid-like mechanical property, and loses its reversible sensing capability. In the temperature range from -60 to 90 °C, the CNT/PDMS composite exhibits good elasticity and reversible sensing behaviors and its modulus, resistivity, and sensing sensitivity decrease with an increasing temperature. At room temperature (30 °C), the CNT/PDMS composite exhibits better mechanical and piezoresistive stability than those at low and high temperatures. Given that environmental temperature changes have significant effects on the sensing performances of conductive polymer composites, the effect of ambient temperature changes must be considered when flexible piezoresistive sensors are designed and fabricated.

On the Interaction between PEDOT:PSS Dispersions and Aluminium Electrodes for Solid State Electrolytic Capacitors

The use of conductive polymers in aluminium electrolytic capacitors prevents leakage and enlarges the temperature use range when compared with their liquid counterparts. PEDOT:PSS is an outstanding candidate due to its tunable properties, i.e., electronic conductivity (10−5 to 103 S/cm), and its high thermal stability. As a result of their synthesis, PEDOT:PSS dispersions are characterized by a low pH value, which can influence pH sensitive materials such as aluminium. However, no work to date has studied the interaction between PEDOT:PSS dispersions and aluminium oxide substrates. In this work, the interface and interaction between PEDOT:PSS and an aluminium electrode were studied for the first time via odd random phase electrochemical impedance spectroscopy and analysed post mortem by SEM and AFM characterization. PEDOT:PSS dispersions at different pH values (1.9, 4.9, 5.8) were applied in a layered manner onto a non-etched aluminium substrate with a grown oxide layer on top, which provided a model system for the analysis of the interface. The analysis showed that the acidic PEDOT:PSS dispersions attacked the aluminium substrate, forming pores on the surface, but had a positive impact on the capacitance of the aluminium oxide/PEDOT:PSS systems. On the other hand, neutral dispersions did not affect the aluminium electrode, but showed poor layer formation properties, and the electrochemical analysis displayed a dispersion of results ranging from capacitive to resistive behaviour.

Sequestration of hazardous alizarin Red S dye from water using mesoporous sponge-PANI composite

In this paper, the performance of the combination of polyaniline, a conductive polymer, and a polyurethane-based dishwashing sponge (sponge/PANI) on the adsorptive removal of Alizarin Red S dye from aqueous solutions was investigated. Firstly, polyurethane-based dishwashing sponges were cut into pieces and then coated by PANI. The sponge/PANI composites were characterized by XRD, SEM-EDX, BET, and FTIR-ATR analysis. Optimum conditions (adsorbent dosage: 0.1 g/50 mL, pH: 6–8, contact time: 120 min, agitation rate: 120 rpm) for adsorption were determined. Adsorption data were applied to different isotherm and kinetic models. According to the isotherm models, Langmuir model was found to be more suitable and the maximum adsorption capacity was found to be 188.68 mg/g at 298 K. According to the adsorption kinetic data, the adsorption process was found to follow the pseudo-second order kinetic model. Meanwhile, from the study on the adsorption mechanism, electrostatic interactions, H-bonding and interlayer force were considered to be the main driving force for adsorption. From the adsorption thermodynamic data, it was found that the adsorption of ARS dye was exothermic ( Δ H o = − 24.00   kJ / mol ) and spontaneous ( Δ G o = − 30.26   kJ / mol at 298   K ). Furthermore, from the reusability studies carried out, it was determined that the prepared adsorbent can be effectively used repeatedly. When the adsorption results were evaluated, it was determined that PANI-coated sponge composites effectively adsorbed Alizarin Red S dye. Moreover, the adsorption efficiency is open to improvement through optimization of surface properties by different methods such as doping.

Review—Recent Progress, Challenges, and Trends in Polymer-Based Wearable Sensors

Abstract Wearable sensors offer a non-invasive, continuous, and personalized approach to monitor various physiological and environmental parameters. Among the various materials used in the fabrication of wearable sensors, polymers have gained significant attention due to their versatile properties, low cost, and ease of integration. We present a comprehensive review of recent advances and challenges in the development of polymer-based wearable sensors. We begin by highlighting the key characteristics of wearable sensors, emphasizing their potential applications and advantages. Subsequently, we delve into the various types of polymers employed for sensor fabrication, such as conductive polymers, elastomers, and hydrogels. The unique properties of each polymer and its suitability for specific sensing applications are discussed in detail. We also address the challenges faced in the development of polymer-based wearable sensors and describes the mechanism of action in these kinds of wearable sensor-capable smart polymer systems. Contact lens-based, textile-based, patch-based, and tattoo-like designs are taken into consideration. Additionally, we paper discuss the performance of polymer-based sensors in real-world scenarios, highlighting their accuracy, sensitivity, and reliability when applied to healthcare monitoring, motion tracking, and environmental sensing. In conclusion, we provide valuable insights into the current state of polymer-based wearable sensors, their fabrication techniques, challenges, and potential applications

Interfacial modification mechanism construction enabled red phosphorous anode for ultra-long life lithium-ion batteries

Red phosphorus for lithium-ion batteries (LIBs) is considered to be promising electrode material due to the high theoretical capacity and moderate working potential. However, the enormous volumetric expansion and intrinsic poor electrical conductivity result in poor interfacial stability and sluggish reaction kinetics. Herein, different functional conductive polymers are introduced to modify the interface, aiming to improve the interfacial compatibility and mechanical stability between red phosphorus and matrix materials. The Cobalt polyphthalocyanine (CoPPc)/polydopamine (PD) hybrid interface not only facilitates electron transfer within the system, but also accommodate the volume expansion of red phosphorus. Consequently, the novel P/CoPPc@PD anode achieves a stable specific capacity of 650 mAh g−1 after 580 cycles at 200 mA g−1, and a discharge capacity of 385 mAh g−1 at 5.0 A g−1 even after 10,000 cycles, demonstrating outstanding long-term cycling stability and rate performance.