PSS Polymer Research Articles

Bimetallic PdPt nanoparticle-incorporated PEDOT:PSS/guar gum-blended membranes for enhanced CO2 separation.

To address the escalating demand for efficient CO2 separation technologies, we introduce novel membranes utilizing natural polymer guar gum (GG), conjugate polymer (poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)) PEDOT:PSS, and bimetallic PdPt nanoparticles. Bimetallic PdPt nanoparticles were synthesized using the wet chemical method and characterized using X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) techniques. The morphologies, chemical bonds, functional groups, and mechanical properties of the fabricated membranes were characterized using various techniques. Through meticulous fabrication and characterization, the binary blended membranes demonstrated enhanced homogeneity and smoothness in their structure, attributed to the interaction between the polymers, and superior CO2 permeability due to the amphiphilic nature of the PEDOT:PSS polymer. Gas separation experiments performed using H2, N2, and CO2 gases confirmed that the 20% PEDOT:PSS/GG blended membranes showed the best performance with sufficient mechanical properties. Moreover, the results demonstrated an increase of 172% in CO2 permeability and 138% in CO2/H2 selectivity, respectively. Furthermore, integrating bimetallic PdPt nanoparticles provided an additional 197% increase in CO2/H2 selectivity, owing to the unique catalytic activities of noble metal nanoparticles. The study not only underscores the transformative potential of polymer blending and noble metal engineering, but also highlights the significance of using natural polymers for sustainable environmental solutions.

Negative temperature coefficient effect of TPU/SWCNT/PEDOT:PSS polymer matrices for wearable temperature sensors

Composite-based temperature sensors utilizing the negative temperature coefficient (NTC) effect have gained significant attention across various fields, particularly in healthcare. However, the development of innovative, highly linear, and high-performance NTC-based temperature sensors remains a challenge. In this study, we developed a composite temperature sensor comprising thermoplastic polyurethane (TPU), single-walled carbon nanotubes (SWCNTs), and poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). A series of performance tests demonstrated that the TPU/SWCNT/PEDOT:PSS (TSP) composite effectively monitors temperature variations with both linearity and superior performance, attributed to the synergistic NTC effects of SWCNTs and PEDOT:PSS. This flexible temperature sensor retained its sensing functionality after repeated cycles of temperature fluctuations and multiple bending tests. Moreover, due to the unique properties of CNTs, the TSP sensor exhibited photothermal responses, showing highly sensitive resistance changes upon exposure to infrared radiation. The TSP sensor proved to be effective for various practical applications, including biosignal monitoring through thermal detection, temperature tracking during phone charging, and accurate temperature sensing on curved surfaces. Additionally, non-contact heat detection can be reliably performed regardless of whether tensile stress is applied. These findings underscore the immense potential of TSP sensors for future use in wearable healthcare technologies.

Microbial symbiotic electrobioconversion of carbon dioxide to biopolymer (poly (3-hydroxybutyrate)) via single-step microbial electrosynthesis cell

This study proposes an novel single-stage microbial electrosynthesis system (MES) that bioelectrochemically converts CO2 into poly(3-hydroxybutyrate) (PHB). This innovative approach utilizes a symbiotic co-culture of electroactive acetogenic bacteria and PHB-accumulating bacteria within a single reactor, bypassing the need for separate acetate production and extraction. Systematic optimization of key operational parameters, including applied voltage, carbon source, and cathode material, was conducted to maximize PHB production. Results demonstrate that using a voltage of 2.5 V yielded a 7.14-fold increase in PHB content compared to open circuit conditions. Furthermore, functionalizing the cathode with a conductive and hydrophilic PEDOT: PSS polymer coating significantly enhanced the system’s performance, resulting in a 1.5-fold increase in both acetate and PHB production compared to unmodified carbon felt electrodes. The long-term stability and effectiveness of the co-culture system were validated through comprehensive microbial and metagenomic analyses. Results revealed a significant enrichment of CO2-utilizing electrotrophs within the cathode biofilm, including Acetobacterium and Clostridium. Concurrently, a 4 to 14-fold increase in the relative abundance of PHB-biosynthesizing bacteria, such as Pseudomonas, Rhodobacter and Caulobacter was observed in the planktonic phase. This study offers a promising pathway towards a circular bioeconomy by enabling the valorization of CO2 into valuable bio-based products via single-stage MES, utilizing a symbiotic co-culture.

A new strategy to simultaneously optimize Seebeck coefficient and electrical conductivity of PEDOT:PSS polymer via L-ascorbic acid

PEDOT:PSS flexible thermoelectric materials are promising for future wearable continuous power support, but it remains challenging due to low power factor. Herein, we propose a “one-stone-two-birds” strategy using L-ascorbic acid as the reductant in synthesis of tellurium nanorods and separating agent in in-situ removing PSS chains. L-ascorbic acid reduces Te4+ to Te, supplying inorganic thermoelectric materials with high Seebeck coefficient as fillers to significantly increase the Seebeck coefficient value of PEDOT:PSS. Meanwhile, L-ascorbic acid separates PSS chains from PEDOT chains, resulting in the increase of electrical conductivity at room temperature by ∼360 % due to structure transformation from benzoid structure to the quinoid structure in PEDOT. As a result, the power factor of optimal PEDOT:PSS with Te fillers and L-ascorbic acid treatment is improved significantly by ∼100 times as compared to that of pristine PEDOT:PSS. Finally, a prototype wearable thermoelectric generator was assembled by 18 legs of Te/PEDOT:PSS composites, which demonstrates a high power density of 2.3 μW·cm−2 with good mechanical stability, flexibility and durability. The present study offers a new strategy for rational design of high-performance flexible thermoelectric materials from PEDOT:PSS.

(Invited) Designing Materials for Organic Electrochemical Transistors

Organic electrochemical transistors (OECTs) have gained a renewed interest in the field or bioelectronics and biosensors. OECTs act as amplifiers and therefore provide high signal/noise ratio for detecting a wide range of biomolecules or physiological signals. A critical component of the OECTs is the channel material, which is an organic mixed ionic-electronic conductor (OMIEC). In simpler terms, OMIECs are (semi)conducting polymers that can transport electronic charges (electrons or holes), transport ionic charges, and display a capacitive behavior (reversible doping/dedoping process). Amongst OMIECs, the polyelectrolyte complex PEDOT:PSS has been the most widely used, likely due to its commercial availability and ease of use as a water dispersion. PEDOT:PSS, however, is a black box with a proprietary composition and does not have particularly reactive handles for functionalization. As such, it is difficult to modify its properties for specific applications in biosensing. In this talk, I will describe my team’s work in understanding PEDOT:PSS and methods for modifying it using covalent organic chemistry. Our principal approach is to control the synthesis of the PSS polymer and/or modify it with functional units by using random or block copolymerization. This approach was successfully used to achieve high performance OECT devices and new conductive materials with temperature or light-response.

Ab initio modeling and experimental analysis of electronic conductivity in PEDOT:PSS-PEO films for extrusion-based manufacturing

In this study, a combination of ab initio modeling and experimental analysis is presented to investigate and elucidate the electronic conductivity of films composed of conducting polymer blend PEDOT:PSS-PEO. Detailed density functional theory (DFT) calculations, aligned with experimental data, aided at profound understanding of the chemical composition, band structure, and the mechanical behavior of these composite materials. Systematic evaluation across diverse ratios of PEDOT, PSS, and PEO revealed a pronounced transformation in electronic properties. Specifically, the addition of PEO into the polymer matrix remarkably changes the band gap, with a marked alteration observed near a PEO concentration of 52 wt-%. This adjustment led to a substantial enhancement in the electrical conductivity, exhibiting an increase by a factor of approximately 20, compared to the original PEDOT:PSS polymer. The present investigation determined the crucial role of the PEDOT to PSS ratio in band gap determination, emphasizing its significant impact on the material's electrical conductivity. Concurrently, the mechanical property analysis unveiled a consistent increase in Young's modulus, reaching up to 765.93 MPa with increased PEO content, signifying a notable mechanical stiffening of the blend. The obtained combined theoretical and experimental insights illustrate a detailed perspective on the conductivity anomalies observed in PEDOT:PSS-PEO systems, establishing a robust framework for designing highly conducting and mechanically stable polymer blends. This comprehensive approach elucidates the interplay between chemical composition and electronic behavior, offering a strategic pathway for extrusion-based manufacturing techniques such as Direct Ink Writing (DIW).

A film composed of PEDOT:PSS/PVA as a sensitive medium for pH sensor in optical fiber

In this work, a pH sensitive transducer element attached to a multimode optical fiber section is proposed. The sensitive element is a PEDOT:PSS/PVA composite film that exhibited sensitivity at low pH values in the range of 1–7 pH. The addition of PVA was important for the adhesion process to the optical fiber surface. The morphology of the PEDOT:PSS polymers allowed characterization at pH stimuli that were based on the optical power transmission generated from the interaction of the light propagating in the optical fiber core and the optical fiber section coated with the sensitive film. A sensitivity of −0.05 dB/pH and a linear fit R2 of 0.93 was obtained, the response time was 3 s, while the sensor recovery time was 50 s maintaining stability higher than 10 min.

Improved thermoelectric performance of n-type BiTeSe based composites incorporated with PEDOT: PSS polymer nanoinclusions

Many studies indicated that the thermoelectric performance of n-type Bi2Te2.7Se0.3 (BTS) was much more difficult to be elevated as compared to its p-type counterpart due to the frangible electron mobility of BTS. Here, the BTS based composites were designed and prepared by introducing the nanophase poly (3, 4-ethylidene dioxythiophene): Polystyrene sulfonate (PEDOT: PSS). As a result, due to the adjustment of the transport properties and strengthened energy filtering effect, the decreased electrical resistivity and enhanced thermopower were obtained, thus leading to the significant improvement of power factor in the whole investigated temperature range. Meanwhile, the lattice thermal conductivity of the composites was sharply reduced by enhanced phonon scattering, reaching a minimum of 0.33 W m−1 K−1 (at 300 K). As a result, the larger ZTmax = 1.23 @415 K and higher ZTave = 1.15 (300–500 K) are achieved for the composite sample xPEDOT: PSS/BTS with x = 0.5 wt%. Moreover, our fabricated single-leg device made of composites shows an energy conversion efficiency of 3.03% (at ΔT = 225 K) that is ∼53% higher than that of the same device made of a commercial BTS ingot, demonstrating that incorporation of nanophase PEDOT: PSS in BTS is effective way in improving its thermoelectric performance.

Additive Blending Effects on PEDOT:PSS Composite Films for Wearable Organic Electrochemical Transistors.

Organic electrochemical transistors (OECTs) employing conductive polymers (CPs) have gained remarkable prominence and have undergone extensive advancements in wearable and implantable bioelectronic applications in recent years. Among the diverse arrays of CPs, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is a common choice for the active-layer channel in p-type OECTs, showing a remarkably high transconductance for the high amplification of signals in biosensing applications. This investigation focuses on the novel engineering of PEDOT:PSS composite materials by seamlessly integrating several additives, namely, dimethyl sulfoxide (DMSO), (3-glycidyloxypropyl)trimethoxysilane (GOPS), and a nonionic fluorosurfactant (NIFS), to fine-tune their electrical conductivity, self-healing capability, and stretchability. To elucidate the intricate influences of the DMSO, GOPS, and NIFS additives on the formation of PEDOT:PSS composite films, theoretical calculations were performed, encompassing the solubility parameters and surface energies of the constituent components of the NIFS, PEDOT, PSS, and PSS-GOPS polymers. Furthermore, we conducted a comprehensive array of material analyses, which reveal the intricacies of the phase separation phenomenon and its interaction with the materials' characteristics. Our research identified the optimal composition for the PEDOT:PSS composite films, characterized by outstanding self-healing and stretchable capabilities. This composition has proven to be highly effective for constructing an active-layer channel in the form of OECT-based biosensors fabricated onto polydimethylsiloxane substrates for detecting dopamine. Overall, these findings represent significant progress in the application of PEDOT:PSS composite films in wearable bioelectronics and pave the way for the development of state-of-the-art biosensing technologies.

Methanol detection with Au-nanoparticles decorated-PPyC-SnO2 nanocomposites using PEDOT:PSS polymer by differential pulse voltammetry

In this approach, sensitive development of methanol electrochemical sensor based on Au-nanoparticles decorated polypyrrole carbon with tin dioxide nanocomposites (Au NPs-PPyC-SnO2 NCs) were prepared and deposited onto glassy carbon electrode (GCE) to make sensor probe using PEDOT:PSS polymer as a conducting binder. The newly developed Au NPs-PPyC-SnO2 NCs were prepared through wet chemical and photo-reduction techniques in lab-made experimental scales, resulting in a morphology that promotes electrochemical reactions for detecting unsafe methanol under ambient conditions using three-electrode systems by differential pulse voltammetry (DPV). The sensor exhibited higher sensitivity (4.2373 µAµM-1cm−2), lower limit of detection (LOD; 2.39 ± 0.12 µM), and a wide linear detection range (LDR; 30.0 to 300.0 µM), which measured from the slope of the calibration curve from concentration variation analyses by considering the active surface area of the coated GCE. To validate its practical application, the fabricated Au NPs-PPyC-SnO2 NCs/GCE sensor electrode was tested for several real samples. It was found a satisfactory performance in the detection of methanol that was observed by using the electrochemical DPV technique with the recovery approach for the fabricated Au NPs-PPyC-SnO2 NCs/GCE sensor probe. It has introduced a new route for the sensitive detection of target methanol with gold-decorated nanocomposite materials in the protection of environmental and ecological fields using an electrochemical approach on a large scale.

The brief study of ZnO/PEDOT:PSS counter electrode in DSSC Based on solid electrolyte YSZ

Dye-Sensitized Solar Cell (DSSC) is a photovoltaic technology that is eco-friendly, has affordable costs, an easy fabrication process, and high power conversion efficiency. The application of solid electrolytes in DSSC is a promising option compared to using liquid electrolytes because liquid electrolytes easily cause corrosion on the photoanode and counter electrode. The role of the counter electrode in DSSC is crucial to speed up the electron transfer process to enhance the performance of DSSC devices. Much research on DSSC still uses a lot of platinum and graphene which are relatively expensive and supplies are limited. Therefore, this research will develop a low-cost and easy to fabricate counter electrode made of ZnO/PEDOT:PSS composite. Adding ZnO in PEDOT:PSS polymer can obtain higher catalytic activity, that can accelerate oxidation–reduction reactions to improve the performance of DSSC solar cells. From the results of this study, it can be concluded that the addition of ZnO mass to the ZnO/PEDOT: PSS composite can increase lattice parameters, crystal size, porosity values, and light absorbance. Based on the I-V testing, it shows that the addition of ZnO mass to the ZnO/PEDOT:PSS composite results in the highest efficiency of 3.29%.

High green index electromagnetic interference shields with semiconducting Bi2S3 fillers in a PEDOT:PSS matrix.

Conventional metallic electromagnetic interference (EMI) shields, as well as the emerging 2D material-based shields, meet the shielding effectiveness (SE) needs of most applications. However, their shielding performance is dominated by the reflection of incoming radiation due to their high electrical conductivity, which leads to secondary pollution. This problem is getting exacerbated with the proliferation of electronics and communication networks in modern society. Thus, EMI shields that function dominantly by the absorption of incoming radiation are highly desirable. Such shields would be characterized by a green index, which is the ratio of absorbance over reflectance, close to or greater than one. For nonmagnetic materials, the best way to reduce the undesirable large impedance mismatch is to reduce the effective permittivity of the shield material. Here, we present a new EMI shield with a semiconductor Bi2S3 filler in a conducting PEDOT:PSS polymer matrix, instead of the conventional conductive fillers, to reduce the effective permittivity and demonstrate that even a light loading of only 10% Bi2S3 provides high SE of over 40 dB with a green index value of 0.75. Increasing the filler content to 15 wt% increases the green index close to unity while dropping the SE to 30 dB. The shielding mechanism is explained through electromagnetic parameter measurements and supplemented by density functional theory calculations. This work lays the foundation for the advancement of lightweight and ultrathin green EMI shields with minimum secondary pollution.

Sulfonate-rich polymer intercalated LDH artificial SEI film to enable high-stability Li-S batteries

Constructing a functional solid electrolyte interface (SEI) is of great significance to promote the practical application of lithium-sulfur batteries (LSBs). In this work, we design and synthesize a sulfonate-rich polymer intercalated LDH (LDH@PSS) and obtain organic-inorganic hybrid artificial SEI film on the surface of Li by spin-coating. The PSS intercalated LDH has a large layer spacing, which effectively improves the transfer kinetics of lithium ion. More importantly, the PSS polymer chain with rich sulfonic groups have strong electronegativity and can electrostatically repel polysulfide anions, which effectively suppress the self-discharge behavior caused by the “shuttle effect”. The symmetrical battery using LDH@PSS-Li shows a cycle life of up to 3100 h at 1 mA cm−2current density. In-situ optical tests also further confirm that the modified materials have excellent dendrite inhibition ability. The shuttle current and self-discharge tests show that LDH@PSS-Li can effectively prevent the parasitic reaction between polysulfide and lithium. After 200 cycles at 0.2 C, the battery maintains a reversible capacity of 1032.6 mAh cm−2, with a reduced capacity decay rate from 0.321 % of unprotected Li anode to 0.086 % per cycle. Consequently, LDH@PSS composite material as artificial SEI film has great application potential for the anodic protection of LSBs.

In-situ growth of hydrogen-bonded organic framework on conductive PEDOT:PSS polymer to realize conductivity-enhanced electrochemiluminescence for fabricating ultrasensitive biosensor

Hydrogen-bonded organic frameworks (HOFs) have gradually received research interest in the electrochemiluminescence (ECL) realm for their high porosity, large surface area, low toxicity, and remarkable biocompatibility, whereas the poor electrical conductivity of HOFs limits electrochemical excitation of ECL luminophores to cause low utilization ratio of ECL luminophores. To circumvent the problem, we prepared a conductive HOF composite (H3TATB-HOF/PEDOT:PSS) by in-situ growth of H3TATB-HOF (H3TATB = 2,4,6-tris(4-carboxyphenyl)− 1,3,5-triazine) on highly conductive poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) polymer. Satisfactorily, the ECL intensity of H3TATB-HOF/PEDOT:PSS presented a respective 14.94-time, 4.71-time, and 2.82-time improvement than those of H3TATB monomers, H3TATB aggregates, and H3TATB-HOF, which was mainly attributed to the high-conductivity PEDOT:PSS that facilitated charge transport throughout the H3TATB-HOF/PEDOT:PSS framework, enabling more H3TATB to be excited electrochemically. Considering the H3TATB-HOF/PEDOT:PSS featuring superior ECL properties, an ultrasensitive ECL biosensor for microRNA-21 assay was designed by combining H3TATB-HOF/PEDOT:PSS as an ECL beacon with a 3D DNA walker amplification strategy, exhibiting broad linear range (100 aM to 1 nM) with a low detection limit (45.7 aM). Overall, this work demonstrates that the ECL performance of HOF-based ECL materials can be significantly improved by enhancing electrical conductivity, thus providing a new idea to explore high-efficiency ECL emitters for building high-sensitivity ECL biosensors.

An anti-fouling wearable molecular imprinting sensor based on semi-interpenetrating network hydrogel for the detection of tryptophan in sweat

The challenge of heavy biofouling in complex sweat environments limits the potential of electrochemical sweat sensors for noninvasive physiological assessment. In this study, a novel semi-interpenetrating hydrogel of PSBMA/PEDOT:PSS was engineered by interlacing PEDOT:PSS conductive polymer with zwitterionic PSBMA network. This versatile hydrogel served as the foundation for developing an anti-fouling wearable molecular imprinting sensor capable of sensitive and robust detection of tryptophan (Trp) in complex sweat. The incorporation of PEDOT:PSS conductive polymer into the semi-interpenetrating hydrogel introduced diverse physical crosslinks, including hydrogen bonding, electrostatic interactions, and chain entanglement. This incorporation considerably boosted the hydrogel's mechanical robustness and imparted commendable self-healing property. At the same time, the synergistic coupling between the well-balanced charge of the zwitterionic network and the high conductivity of the PEDOT:PSS polymer facilitated efficient charge transfer. The formation of the desired molecular imprinting membrane of semi-interpenetrating hydrogel was triggered by self-polymerization of dopamine (DA) in the presence of Trp. The designed biosensor demonstrated good sensitivity, selectivity and stability in detecting the target Trp. Notably, it also exhibited exceptional anti-fouling abilities, allowing for accurate Trp detection in complex real sweat samples, yielding results comparable to commercial enzyme-linked immunoassay (ELISA).

Biophysical Electrical and Mechanical Stimulations for Promoting Chondrogenesis of Stem Cells on PEDOT:PSS Conductive Polymer Scaffolds.

The investigation of the effects of electrical and mechanical stimulations on chondrogenesis in tissue engineering scaffolds is essential for realizing successful cartilage repair and regeneration. The aim of articular cartilage tissue engineering is to enhance the function of damaged or diseased articular cartilage, which has limited regenerative capacity. Studies have shown that electrical stimulation (ES) promotes mesenchymal stem cell (MSC) chondrogenesis, while mechanical stimulation (MS) enhances the chondrogenic differentiation capacity of MSCs. Therefore, understanding the impact of these stimuli on chondrogenesis is crucial for researchers to develop more effective tissue engineering strategies for cartilage repair and regeneration. This study focuses on the preparation of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) conductive polymer (CP) scaffolds using the freeze-drying method. The scaffolds were fabricated with varying concentrations (0, 1, 3, and 10 wt %) of (3-glycidyloxypropyl) trimethoxysilane (GOPS) as a crosslinker and an additive to tailor the scaffold properties. To gain a comprehensive understanding of the material characteristics and the phase aggregation phenomenon of PEDOT:PSS scaffolds, the researchers performed theoretical calculations of solubility parameters and surface energies of PSS, PSS-GOPS, and PEDOT polymers, as well as conducted material analyses. Additionally, the study investigated the potential of promoting chondrogenic differentiation of human adipose stem cells by applying external ES or MS on a PEDOT:PSS CP scaffold. Compared to the group without stimulation, the group that underwent stimulation exhibited significantly up-regulated expression levels of chondrogenic characteristic genes, such as SOX9 and COL2A1. Moreover, the immunofluorescence staining images exhibited a more vigorous fluorescence intensity of SOX9 and COL II proteins that was consistent with the trend of the gene expression results. In the MS experiment, the strain excitation exerted on the scaffold was simulated and transformed into stress. The simulated stress response showed that the peak gradually decreased with time and approached a constant value, with the negative value of stress representing the generation of tensile stress. This stress response quantification could aid researchers in determining specific MS conditions for various materials in tissue engineering, and the applied stress conditions could be further optimized. Overall, these findings are significant contributions to future research on cartilage repair and biophysical ES/MS in tissue engineering.

Novel dry EEG electrode with composite filler of PEDOT:PSS and carbon particles.

We have developed a novel composite filler with Poly(3,4-ethylenedioxythiophene) : poly(styrenesulfonic acid) (PEDOT:PSS), a biocompatible organic conductive polymer, adsorbed on carbon particles for biological electrodes. This composite filler enables to fabricate high-performance biological electrodes simply by adding it to resin in the same way as conventional conductive fillers. The fabricated electrodes achieve ion exchange properties similar to those of PEDOT:PSS polymers and therefore low skin and electrode contact impedance. Electroencephalogram (EEG) measurements show that these electrodes capture various brain activities and exhibit high correlation (≥ 0.9) to commercially available wet and AgCl electrodes. Additionally, each electrode can be molded into various shapes and structures while retaining its electrode characteristics. Therefore, the proposed electrode is promising for EEG measurement, which requires high comfort and signal quality.

Combining PEDOT:PSS Polymer Coating with Metallic 3D Nanowires Electrodes to Achieve High Electrochemical Performances for Neuronal Interfacing Applications.

This study presents a novel approach to improve the performance of microelectrode arrays (MEAs) used for electrophysiological studies of neuronal networks. The integration of 3D nanowires (NWs) with MEAs increases the surface-to-volume ratio, which enables subcellular interactions and high-resolution neuronal signal recording. However, these devices suffer from high initial interface impedance and limited charge transfer capacity due to their small effective area. To overcome these limitations, the integration of conductive polymer coatings, poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) is investigated as a mean of improving the charge transfer capacity and biocompatibility of MEAs. The study combines platinum silicide-based metallic 3D nanowires electrodes with electrodeposited PEDOT:PSS coatings to deposit ultra-thin (<50 nm) layers of conductive polymer onto metallic electrodes with very high selectivity. The polymer-coated electrodeswerefully characterized electrochemically and morphologically to establish a direct relationship between synthesis conditions, morphology, and conductive features. Results show that PEDOT-coated electrodes exhibit thickness-dependent improved stimulation and recording performances, offering new perspectives for neuronal interfacing with optimal cell engulfment to enable the study of neuronal activity with acute spatial and signal resolution at the sub-cellular level.

Investigation of Electrical and Wearing Properties of Wool Fabric Coated with PEDOT:PSS.

The way to improve the properties (resistance to washing, delamination, and rubbing off) of the PEDOT:PSS coating applied on wool fabric without reduction of its electrical conductivity by introducing a commercially available combination of low formaldehyde content melamine resins into the printing paste is presented in this paper. Primarily, to improve the hydrophilicity and dyeability of wool fabric, the samples were modified using low-pressure nitrogen (N2) gas plasma. Two commercially available PEDOT:PSS dispersions were used to treat wool fabric by the exhaust dyeing and screen printing methods, respectively. Spectrophotometric measurements of the color difference (ΔE*ab) and visual evaluation of woolen fabric dyed and printed with PEDOT:PSS in different shades of the blue color showed that the sample modified with N2 plasma obtained a more intense color compared to the unmodified one. SEM was used to examine the surface morphology and a cross-sectional view of wool fabric that had undergone various modifications. SEM image shows that the dye penetrates deeper into the wool fabric after plasma modification using dyeing and coating methods with a PEDOT:PSS polymer. In addition, with a Tubicoat fixing agent, HT coating looks more homogeneous and uniform. The chemical structure spectra of wool fabrics coated with PEDOT:PSS were investigated using FTIR-ATR characterization. The influence of melamine formaldehyde resins on the electrical properties, resistance to washing, and mechanical effects of PEDOT:PSS treated wool fabric was also evaluated. The resistivity measurement of the samples containing melamine-formaldehyde resins as an additive did not show a significant decrease in electrical conductivity, while the electrical conductivity was maintained after the washing and rubbing test as well. The best results of electrical conductivity for investigated wool fabrics before and after washing and mechanical action were determined for samples subjected to the combined processing-surface modification by low-pressure N2 plasma, dyeing by exhaust with PEDOT:PSS, and coating by the screen-printing method of PEDOT:PSS and a 3 wt.% melamine formaldehyde resins mixture.

Synthesis of PEDOT: PSS thin film doped with silver nanoparticles via green approach and study their refractive indices and dispersive parameters using Wemple–DiDomenico (WDD) single oscillator model

Silver nanoparticles (AgNPs) synthesised via green synthesis using clove extract were incorporated into PEDOT:PSS polymers using the chemical solution deposition technique (CSD), and the effect of surface plasmon resonance in the nanocomposites was investigated. To assess the effect of Silver nanoparticles (AgNPs) (and surface plasmon resonance) on the polymer, TEM, UV–Visible spectroscopy, FTIR, Ellipsometry, and Photoluminescence are used. The surface plasmon peak of the curves in UV–Vis spectroscopy study of these films has shifted towards the infrared region, which may be useful in increasing the efficiency of optical devices. The optical band gap calculated using UV–Vis results reduced from 1.77eV for pure PEDOT: PSS to 1.53eV for the nanocomposite. Ellipsometry data is used to calculate Ψ, Δ values and thickness of films. The Wemple-DiDomenico (WDD) single oscillator model was used to analyse and estimate the dispersion parameters of these films. Refractive indices the films were calculated in the range 1.256–1.643 using the Ellipsometry data.