The application of transistors based on poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonic acid) (PEDOT:PSS) in chemical and biological sensing is reviewed. These devices offer enormous potential for facile processing of small, portable, and inexpensive sensors ideally suited for point-of-care analysis. They can be used to detect a wide range of analytes for a variety of possible applications in fields such as health care (medical diagnostics), environmental monitoring (airborne chemicals, water contamination, etc.), and food industry (smart packaging). Organic transistors are excellent candidates to act as transducers because they have the ability to translate chemical and biological signals into electronic signals with high sensitivity. Furthermore, fuctionalization of PEDOT:PSS films with a chemical or biological receptor can lead to high specificity. The advantages of using PEDOT:PSS transistors are described, and applications are presented for sensing analytes in both gaseous and aqueous environments. 相似文献
As a representing conducting polymer, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) has been widely employed in organic electronics. However, the electrical conductivity for pristine PEDOT:PSS is only between 0.1 and 0.5 S/cm. In order to enhance the conductivity, the silver nanowires (Ag NWs) were synthesized to dope PEDOT:PSS. It was found the electrical conductivity of PEDOT:PSS was improved to about 200 S/cm with Ag NWs. When double-wall carbon nanotube (DWCNT) was employed together with Ag NWs, the electrical conductivity was further improved to over 2800 S/cm. We proposed the synergistic working model between Ag NWs and CNTs for such enhancement. In this work, UV-vis-NIR spectra and SEM images were also employed to investigate the mechanism of electrical conductivity enhancement. 相似文献
Stretchable conductive hydrogels have received significant attention due to their possibility of being utilized in wearable electronics and healthcare devices. In this work, a semi-interpenetrating polymer network (SIPN) strategy was employed to fabricate a set of flexible, stretchable and conductive composite hydrogels composed of polyvinyl alcohol (PVA) in the presence of glutaraldehyde as the crosslinker, HCl as the catalyst and poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) as the conductive medium. The results from FTIR, Raman, SEM and TGA indicate that a chemical crosslinking network and interactions of PVA and PEDOT:PSS exist in the SIPN hydrogels. The swelling ratio of hydrogels decreased with increasing content of PEDOT:PSS. Due to the chemical crosslinking network and interactions of PVA and PEDOT:PSS, PVA networks semi-interpenetrated with PEDOT:PSS exhibited excellent tensile and compression properties. The tensile strength and elongation at breakage of the composite hydrogels with 0.14 wt% PEDOT:PSS were 70 KPa and 239%, respectively. The compression stress of the composite hydrogels with 0.14 wt% PEDOT:PSS at a strain of 50% was about 216 KPa. The electrical conductivity of the hydrogels increased with increasing PEDOT:PSS content. The flexible, stretchable and conductive properties endow the composite hydrogel sensor with a superior gauge factor of up to 4.4 (strain: 100%). Coupling the strain sensing capability to the flexibility, good mechanical properties and high electrical conductivity, we consider that the designed PVA/PEDOT:PSS composite hydrogels have promising applications in wearable devices, such as flexible electronic skin and sensitive strain sensors. 相似文献
Highly conductive poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonic acid)(PEDOT:PSS) has been explored to fabricate flexible and stretchable conductors. Generally, PEDOT:PSS transparent anodes are prepared by spin-coating method. In this article, we adopt a method by dropping PEDOT:PSS aqueous solution on the PET plastic substrate to fabricate flexible electrodes. Compared with spin coating, drop-coating is simple and cost-effective with large-area fabrications. Through this method, we fabricated highly transparent conductive electrodes and systematically studied their electrical, optical, morphological and mechanical properties. With dimethyl sulfoxide/methanesulfonic acid(DMSO/MSA) treated PEDOT:PSS electrode,bendable devices based on non-fullerene system displayed an open-circuit voltage of 0.925 V, a fill factor of 70.74%, and a high power conversion efficiency(PCE) of 10.23% under 100 mW cm~(-2) illumination, which retained over 80% of the initial PCE value after 1000 bending cycles. Based on the findings, drop-coated PEDOT:PSS electrodes exhibited high suitability for the development of large-area and high-efficiency printed solar cell modules in the future. 相似文献
Highly conductive poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) films as transparent electrodes for organic light‐emitting diodes (OLEDs) are doped with a new solvent 1,3‐dimethyl‐2‐imidazolidinone (DMI) and are optimized using solvent post‐treatment. The DMI doped PEDOT:PSS films show significantly enhanced conductivities up to 812.1 S cm−1. The sheet resistance of the PEDOT:PSS films doped with DMI is further reduced by various solvent post‐treatment. The effect of solvent post‐treatment on DMI doped PEDOT:PSS films is investigated and is shown to reduce insulating PSS in the conductive films. The solvent posttreated PEDOT:PSS films are successfully employed as transparent electrodes in white OLEDs. It is shown that the efficiency of OLEDs with the optimized DMI doped PEDOT:PSS films is higher than that of reference OLEDs doped with a conventional solvent (ethylene glycol). The results present that the optimized PEDOT:PSS films with the new solvent of DMI can be a promising transparent electrode for low‐cost, efficient ITO‐free white OLEDs.
Newly synthesised fluorescent chemosensor ADDTU contains the thiourea receptor connected to the acridinedione (ADD) fluorophore via a covalent bond, giving rise to a fluorophore-receptor motif. In this fluorescent chemosensor, the anion recognition takes place at the receptor site which result in the concomitant changes in the photophysical properties of a ADD fluorophore by modulation of photoinduced electron transfer (PET) process. The binding ability of these sensor with the anions F(-), Cl(-), Br(-), I(-), HSO(4)(-), ClO(4)(-), AcO(-), H(2)PO(4)(-) and BF(4)(-) (as their tetrabutylammounium salts) in acetonitrile were investigated using UV-vis, steady state and time-resolved emission techniques. ADDTU system allows for the selective fluorescent sensing of AcO(-), H(2)PO(4)(-) and F(-) over other anions in acetonitrile. 相似文献
We report the synthesis, structural characterization, and electrical transport properties of free-standing single-crystal CoSi nanowires synthesized via a single-source precursor route. Nanowires with diameters of 10-150 nm and lengths of greater than 10 mum were synthesized through the chemical vapor deposition of Co(SiCl(3))(CO)(4) onto silicon substrates that were covered with 1-2 nm thick SiO(2). Transmission electron microscopy confirms the single-crystal structure of the cubic CoSi. X-ray absorption and emission spectroscopy confirm the chemical identity and show the expected metallic nature of CoSi, which is further verified by room-temperature and low-temperature electrical transport measurements of nanowire devices. The average resistivity of CoSi nanowires is found to be about 510 muOmega cm. Our general and rational nanowire synthesis approach will lead to a broad class of silicide nanowires, including those metallic materials that serve as high-quality building blocks for nanoelectronics and magnetic semiconducting Fe(1-x)Co(x)Si suitable for silicon-based spintronics. 相似文献
CQD/PEDOT:PSS composites were prepared via the hydrothermal method from glucose carbon quantum dots (CQDs) and an aqueous solution of PEDOT:PSS conducting polymer and their electrical and optical properties were investigated. The morphology and structure of these samples were investigated by AFM, SEM, EDX, and EBSD. It was found that the CQDs and CQD/PEDOT:PSS composites had a globular structure with globule sizes of ~50–300 nm depending on the concentration of PEDOT:PSS in these composites. The temperature dependence of the resistivity was obtained for the CQD/PEDOT:PSS (3%, 5%, 50%) composites, which had a weak activation character. The charge transport mechanism was discussed. The dependence of the resistivity on the storage time of the CQD/PEDOT:PSS (3%, 5%, 50%) composites and pure PEDOT:PSS was obtained. It was noted that mixing CQDs with PEDOT:PSS allowed us to obtain better electrical and optical properties than pure CQDs. CQD/PEDOT:PSS (3%, 5%, 50%) composites are more conductive composites than pure CQDs, and the absorbance spectra of CQD/PEDOT:PSS composites are a synergistic effect of interaction between CQDs and PEDOT:PSS. We also note the better stability of the CQD/PEDOT:PSS (50%) composite than the pure PEDOT:PSS film. CQD/PEDOT:PSS (50%) composite is promising for use as stable hole transport layers in devices of flexible organic electronics. 相似文献
The interaction between poly(3,4-ethylene dioxythiophene) doped with poly(styrene sulfonate) (PEDOT:PSS) and cellulosic fibers
was characterized in order to obtain further understanding of the conductivity properties of the modified cellulosic fiber
material. Microcrystalline cellulose (MCC) was used as a model surface to study the adsorption behavior at various pH and
salt concentrations, while samples of low-conductivity paper, normally used for the production of electrical insulation papers,
were dipped into PEDOT:PSS dispersion and air-dried for X-ray photoelectron spectroscopy (XPS) studies. The results showed
a strong interaction between the MCC and PEDOT:PSS, which implied a broad molecular distribution of the conducting polymer.
With increasing pH, less amount of the conducting polymer was adsorbed whereas the amount adsorbed passed through a maximum
value with varying salt concentration. Zeta potential measurement and polyelectrolyte titration were used to determine the
surface charge of both suspended MCC particles and dispersed PEDOT:PSS at various pH levels and salt concentrations. Dip-coated
paper samples exhibited two peaks in the S(2p) XPS spectra at 168–169 and 164–165 eV which correspond to the sulfur signals
of sulfonate (in PSS) and in thiophene (in PEDOT), respectively. It was found that the PEDOT:PSS with a ratio of 1:2.5 was
adsorbed more in the base paper than that with a ratio of 1:6. The PEDOT:PSS ratio on the surface of the cellulosic material
was higher than that in the bulk liquid for all samples. The results indicated that PEDOT was preferentially adsorbed rather
than PSS. The degree of washing of the conducting polymer did not significantly affect the PEDOT enhancement on the surface. 相似文献
Highly conductive microfibers made of poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT/PSS) were fabricated by wet-spinning and subsequent dip-treatment in ethylene glycol. The electrical conductivity of the PEDOT/PSS microfibers with a diameter of ca. 5 μm was significantly increased from 74 S cm−1 to 467 S cm−1 by the dip-treatment in 3 min. The result was explained by removal of insulating PSS from the surface of the PEDOT/PSS grains and crystallization of PEDOT, which led to the formation of large numbers of higher conductive grains that enhanced the transport of charge carriers in the microfiber. The mechanical properties of the microfibers were also improved by the dip-treatment where Young’s modulus and tensile strength increased from 3.2 GPa and 94 MPa to 4.0 GPa and 130 MPa, respectively. 相似文献
We report the electrochemical deposition of poly(pyrrolepropylic acid) nanowires, their covalent modification with antibodies
and their conversion into potential functional sensor devices. The nanowires and the devices were characterised by optical
microscopy, fluorescence microscopy, electron microscopy and electrical measurements. Fluorescence images, current–voltage
(I–V) profiles and real-time sensing measurements demonstrated a rapid and highly sensitive and selective detection of human serum
albumin (HSA), a substance that has been used to diagnose incipient renal disease. The detection is based on the selective
binding of HSA onto anti-HSA that is covalently attached to the nanowires. The binding changes the electrical properties of
the nanowires thus enabling the real-time detection. Whilst the utility of the research was demonstrated for protein binding/detection,
the technology could easily be designed for the detection of other analytes by the modification of polymer nanowires with
other analyte-specific molecules/biomolecules. Therefore, the technology has the potential to positively impact broad analytical
applications in the biomedical, environmental and other sectors.
Figure Real-time dynamic current response on sequential exposure of buffer, bovine serum albumin (BSA) and human serum albumin (HSA)
onto anti-HSA modified poly (pyrrolepropylic acid) nanowires. Fluorescence images of poly(pyrrolepropylic acid) nanowire (top
right) and polypyrrole nanowire control (bottom right) after sequential treatment with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide
hydrochloride (EDC), anti HSA and fluorophore-labeled HSA. 相似文献
Herein, a route to produce highly electrically conductive doped hydroxymethyl functionalized poly(3,4-ethylenedioxythiophene) (PEDOT) films, termed PEDOT(OH) with metal-like charge transport properties using a fully solution processable precursor polymer is reported. This is achieved via an ester-functionalized PEDOT derivative [PEDOT(EHE)] that is soluble in a range of solvents with excellent film-forming ability. PEDOT(EHE) demonstrates moderate electrical conductivities of 20–60 S cm−1 and hopping-like (i.e., thermally activated) transport when doped with ferric tosylate (FeTos3). Upon basic hydrolysis of PEDOT(EHE) films, the electrically insulative side chains are cleaved and washed from the polymer film, leaving a densified film of PEDOT(OH). These films, when optimally doped, reach electrical conductivities of ≈1200 S cm−1 and demonstrate metal-like (i.e., thermally deactivated and band-like) transport properties and high stability at comparable doping levels. 相似文献
Novel structures comprised of GaAs nanowire arrays conformally coated with conducting polymers (poly(3,4‐ethylenedioxythiophene) (PEDOT) or poly(3,4‐ethylenedioxythiophene‐co‐3‐thiophene acetic acid) display both sensitivity and selectivity to a variety of volatile organic chemicals. A key feature is room temperature operation, so that neither a heater nor the power it would consume, is required. It is a distinct difference from traditional metal oxide sensors, which typically require elevated operational temperature. The GaAs nanowires are prepared directly via self‐seeded metal–organic chemical deposition, and conducting polymers are deposited on GaAs nanowires using oxidative chemical vapor deposition (oCVD). The range of thickness for the oCVD layer is between 100 and 200 nm, which is controlled by changing the deposition time. X‐ray diffraction analysis indicates an edge‐on alignment of the crystalline structure of the PEDOT coating layer on GaAs nanowires. In addition, the positive correlation between the improvement of sensitivity and the increasing nanowire density is demonstrated. Furthermore, the effect of different oCVD coating materials is studied. The sensing mechanism is also discussed with studies considering both nanowire density and polymer types. Overall, the novel structure exhibits good sensitivity and selectivity in gas sensing, and provides a promising platform for future sensor design.