PSS Fibers Research Articles

Highly conductive wet-spun PEDOT:PSS fibers for applications in electronic textiles

PEDOT:PSS fibers with outstanding electrical and mechanical properties were fabricated and their use in a variety of electronic textile applications was demonstrated.

Continuous wet-spinning of flexible and water-stable conductive PEDOT: PSS/PVA composite fibers for wearable sensors

Abstract A conductive composite fiber of poly(3,4-ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT: PSS) and polyvinyl alcohol (PVA) was synthesized via a wet-spinning method. Especially, conductivity loss owing to the addition of PVA was compensated by using a solvent treatment method with ethylene glycol (EG). Compared with pristine PEDOT: PSS fibers, PEDOT: PSS/PVA/EG conductive composite fibers exhibited enhanced flexibility. The optimal tensile strength and elongation at break, 210 ± 5 MPa and 26 ± 1.5% respectively, were obtained for the conductive fibers with the addition of 20 wt% PVA and 10 wt% EG. Meanwhile, the resultant composite fiber revealed a good recovery behavior of the strain and electroconductivity within the strain of 20%. PEDOT: PSS composite fibers reveal a good durability of electroconductivity in water even under a strain. A series of strain sensing fabrics were designed based on the composite fibers. Results of various proof-of-concept experiments indicated that this PEDOT: PSS/PVA/EG composite conductive fiber is a promising candidate for flexible intelligent textiles, which can be used for fast response and sensitive wearable sensors for monitoring body motions and real-time health.

Human sweat monitoring using polymer-based fiber

Lightweight nano/microscale wearable devices that are directly attached to or worn on the human body require enhanced flexibility so that they can facilitate body movement and overall improved wearability. In the present study, a flexible poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) fiber-based sensor is proposed, which can accurately measure the amount of salt (i.e., sodium chloride) ions in sweat released from the human body or in specific solutions. This can be performed using one single strand of hair-like conducting polymer fiber. The fabrication process involves the introduction of an aqueous PEDOT:PSS solution into a sulfuric acid coagulation bath. This is a repeatable and inexpensive process for producing monolithic fibers, with a simple geometry and tunable electrical characteristics, easily woven into clothing fabrics or wristbands. The conductivity of the PEDOT:PSS fiber increases in pure water, whereas it decreases in sweat. In particular, the conductivity of a PEDOT:PSS fiber changes linearly according to the concentration of sodium chloride in liquid. The results of our study suggest the possibility of PEDOT:PSS fiber-based wearable sensors serving as the foundation of future research and development in skin-attachable next-generation healthcare devices, which can reproducibly determine the physiological condition of a human subject by measuring the sodium chloride concentration in sweat.

Effect of Drawing on the Electrical, Thermoelectrical, and Mechanical Properties of Wet-Spun PEDOT:PSS Fibers

New electrically conducting and mechanically robust fibers and yarns are needed as building blocks for emerging textile devices. In this work, we describe a continuous wet-spinning process for the ...

Fast and scalable wet-spinning of highly conductive PEDOT:PSS fibers enables versatile applications

Here, we report a one-step method to produce highly conducting poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) fibers that enables applications in fast response and highly sensitive touch sensors, body moisture monitoring, and long fiber-shaped supercapacitors.

Highly Conductive Hydrogel Polymer Fibers toward Promising Wearable Thermoelectric Energy Harvesting.

The requirement of a portable electron is functioning as a driving force for a wearable energy instrument. Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), as one of the most promising organic electron materials, has been widely studied in energy conversion devices. However, the efforts for PEDOT:PSS fibers are insufficient to boost the development of wearable thermoelectric energy harvesting. Here, a highly conductive p-type PEDOT:PSS fiber was produced by gelation process, which was 3 orders of magnitude higher than that of previous hydrogel fibers. Surprisingly, a post-treatment with organic solvents such as ethylene glycol and dimethyl sulfoxide tripled their electrical conductivity with an only 5% decreased Seebeck coefficient, consequently leading to an optimized thermoelectric power factor. Furthermore, we assembled a p-n-type thermoelectric device connecting five pairs of p-type PEDOT:PSS fibers and n-type carbon nanotube fibers. This fiber-based device displayed an acceptable output voltage of 20.7 mV and a power density of 481.2 μW·cm-2 with a temperature difference of ∼60 K, which might pave the way for the development of organic thermoelectric fibers for wearable energy harvesting.

Highly-wrinkled reduced graphene oxide-conductive polymer fibers for flexible fiber-shaped and interdigital-designed supercapacitors

Flexible supercapacitors have attracted great interest due to outstanding flexibility and light weight. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) fibers have the great potential in using as electrodes for flexible supercapacitors due to the good flexibility. However, the reported conductivity and specific capacitance of these PEDOT: PSS fibers are not very high, which limit their electrochemical performances. In this work, composite fibers of reduced graphene oxide(rGO)-PEDOT: PSS with a highly-wrinkled structure on the surface and pores inside are prepared by wet spinning. The fibers with different ratios of graphene to PEDOT:PSS show a distinctly enhanced conductivity up to ca. 590 S·cm−1 and high strength up to ca. 18.4 MPa. Meanwhile, the composite fibers show an improved electrochemical performances, including a high specific areal capacitance of 131 mF cm−2 and high specific areal energy density of 4.55 μWh·cm−2. The flexible supercapacitors including fiber-shaped supercapacitors and interdigital designed supercapacitors not only could work in different bending states without obvious capacitance decay, but also have small leakage current. The interdigital design can further improve the performances of composite fibers with high capacitance and high utilization compared with traditional parallel connected structure.

Twisted yarns for fiber-shaped supercapacitors based on wetspun PEDOT:PSS fibers from aqueous coagulation

Twisted yarns of wetspun PEDOT:PSS fibers from aqueous coagulation are prepared and used for fiber-shaped supercapacitors with excellent performances.

Knitted Strain Sensor Textiles of Highly Conductive All-Polymeric Fibers.

A scaled-up fiber wet-spinning production of electrically conductive and highly stretchable PU/PEDOT:PSS fibers is demonstrated for the first time. The PU/PEDOT:PSS fibers possess the mechanical properties appropriate for knitting various textile structures. The knitted textiles exhibit strain sensing properties that were dependent upon the number of PU/PEDOT:PSS fibers used in knitting. The knitted textiles show sensitivity (as measured by the gauge factor) that increases with the number of PU/PEDOT:PSS fibers deployed. A highly stable sensor response was observed when four PU/PEDOT:PSS fibers were co-knitted with a commercial Spandex yarn. The knitted textile sensor can distinguish different magnitudes of applied strain with cyclically repeatable sensor responses at applied strains of up to 160%. When used in conjunction with a commercial wireless transmitter, the knitted textile responded well to the magnitude of bending deformations, demonstrating potential for remote strain sensing applications. The feasibility of an all-polymeric knitted textile wearable strain sensor was demonstrated in a knee sleeve prototype with application in personal training and rehabilitation following injury.

One‐Step Wet‐Spinning Process of Poly(3,4‐ethylenedioxythiophene):Poly(styrenesulfonate) Fibers and the Origin of Higher Electrical Conductivity

AbstractA simplified wet‐spinning process for the production of continuous poly (3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) fibers is reported. Conductivity enhancement of PEDOT:PSS fibers up to 223 S cm−1 has been demonstrated when these fibers are exposed to ethylene glycol as a post‐synthesis processing step. In a new spinning approach it is shown that by employing a spinning formulation consisting of an aqueous blend of PEDOT:PSS and poly(ethlylene glycol), the need for post‐spinning treatment with ethylene glycol is eliminated. With this approach, 30‐fold conductivity enhancements from 9 to 264 S cm−1 are achieved with respect to an untreated fiber. This one‐step approach also demonstrates a significant enhancement in the redox properties of the fibers. These improvements are attributed to an improved molecular ordering of the PEDOT chains in the direction of the fiber axis and the consequential enrichment of linear (or expanded‐coil like) conformation to preference bipolaronic electronic structures as evidenced by Raman spectroscopy, solid‐state electron spin resonance (ESR) and in situ electrochemical ESR studies.

Tensile Strength and Conductive Performance of PVA & PEDOT/PSS Blended Fiber

An electroconductive polymer, poly-3,4-ethylenedioxithiophene⁄poly-styrenesulphonic acid (PEDOT⁄PSS) is noticed because it has high generality, electroconductivity, and transparency. We are considering practicability of a cloth sensing device made of electroconductive polymer fibers. However, as the tensile strength of pure PEDOT⁄PSS fiber is low, it is not suitable for fabricating devices. We examined a possibility of coexisting of high conductivity and high strength by blend fibers consisting of an electroconductive polymer and another polymer (polyvinyl alcohol: PVA). A tensile strength of the PEDOT⁄PSS and PVA blend fibers was about twice as that of the pure PEDOT⁄PSS fiber. The electroconductivity of the blend fibers also increased several times despite of decreasing amount of conductive polymer. The Raman spectrum revealed that the comformation of PEDOT was changed into a linear or expanded coil comformation by combining with PVA.