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Carbon nanotubes have been the subject of extensive research during the past decade because of their exceptional properties. These tiny nanostructures have eventually paved their way into the exciting and promising field of organic electronics, which is expected to dominate the area of low cost and flexible electronics in the near future. We have prepared multiwall carbon nanotube (MWNT) and poly(3,4-ethylenedioxythiophene):poly(styrenesulphonic acid) (PEDOT:PSS) based nanocomposites using different concentrations of MWNTs. These nanocomposites have been characterized using SEM, AFM, absorption spectroscopy, and electrical characterization methods. The SEM micrographs clearly reveal that the nanotubes are quasi uniformly dispersed in huge quantities throughout the polymer matrix. They also show the wetting of the nanotubes by the polymer. It is observed that the solution processed MWNT–PEDOT:PSS nanocomposite based films exhibit improved, higher current, and lower turn-on voltage as compared to pure PEDOT:PSS based films. On the basis of percolation theory, a low electrical percolation threshold value of 0.1 wt% was obtained for this nanocomposite system, signifying the formation of a continuous conductive network at a very low MWNT concentration. The ease of fabrication of the nanocomposite (solution processed), higher current, lower turn-on voltage and low electrical percolation threshold value, make it an excellent candidate for flexible electronics applications, which will dominate the electronics scenario in the near future.

It has been demonstrated that high efficiency and brightness can be achieved in phosphorescent organic light-emitting diodes (PHOLEDs) by using molybdenum oxide (MoO₃)/poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) as dual hole injection layers (HILs) on indium tin oxide (ITO) substrate. The dual HILs were simply fabricated by spin-coating PEDOT:PSS solution on a thin MoO₃ layer deposited by vacuum thermal evaporation. This work reveals that PEDOT:PSS coating on MoO₃ resulted in a smoother surface, simultaneously MoO₃ lamella prevented acid corrosion of PEDOT:PSS on ITO. Meanwhile, with the insertion of PEDOT:PSS and MoO₃ as HILs between anode and hole transporting layer (HTL), the energy barrier has been reduced and gave rise to effective hole injection. OLEDs with dual HILs resulted in the maximum current efficiency (CE) of 61.3 cd A${}^{-1}$ and maximum luminance of 112200 cd cm${}^{-2}$, which showed a superior performance compared to those devices with single HIL of PEDOT:PSS or MoO₃. Our results proved the composition of PEDOT:PSS and MoO₃ as HILs were beneficial for high performance OLEDs.

A flexible organic light-emitting device (OLED) was produced using copper nanowire (CuNW) film as anode and Graphene oxide (GO)/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) film as anode buffer layer. Compared with other transparent conductive films (TCFs), CuNWs are low cost, easy to fabricate, and compatible with flexible substrates over a large area. Due to these advantages, CuNWs are showing greater and greater promise for the next generation of TCF. Modified by PEDOT:PSS, the conductivity and work function of the CuNW film can be dramatically enhanced. However, PEDOT:PSS is highly acidic and easy to corrode the CuNW film, which will reduce maximum luminous brightness and current efficiency of the OLED. In this paper, GO/PEDOT:PSS was used as anode buffer layer to modify the CuNW anode and the composite transparent electrode exhibited excellent optoelectrical properties. The driving voltage of the OLED with CuNW/PEDOT:PSS is 6.2V, and the maximum luminous brightness is 2737.2cd/m². The driving voltage of the OLED with CuNW/GO/PEDOT:PSS anode was reduced to 5.1V, and the maximum luminous brightness was improved to 3007.4cd/m².

In this study, GO and GO-PEDOT:PSS nanocomposite films were prepared by using the modified Hummer method and spin-coating, respectively. GO-PEDOT:PSS films with different weight ratios of GO (0.015, 0.03, 0.045 and 0.06) were prepared to study the effect of the GO additive on nitrogen dioxide (NO₂) sensing performance. XRD and AFM were used to determine the crystal structure and the topography of the GO-PEDOT:PSS films. The effects of GO concentration and temperature on electrical conductivity and the change in activation energy of PEDOT:PSS films were also investigated. The findings show that as the temperature rises, the electrical resistance reduces, and as the concentration increases, the activation energy decreases.

We have investigated the dependence of device characteristics of bulk-heterojunction organic thin-film solar cells on the concentration of glycerol and sorbitol addition in poly(3,4-ethylenedioxy thiophene):poly(4-styrene sulfonate) (PEDOT:PSS) solutions for fabricating buffer layers. The device structure is ITO/buffer/regioregular poly(3-hexylthiophene) (P3HT):[6,6]-phenyl C₆₁-butyric acid methylester (PCBM)/Al. Glycerol addition is effective for increasing power conversion efficiency (PCE) from 1.25 to 1.41% because of the increase in short-circuit current density (J_sc) without decreasing open-circuit voltage (V_oc). On the other hand, sorbitol addition decreases PCE from 1.25 to 1.04%, owing to the decrease in V_oc. This difference in V_oc behavior is ascribed to different work function of PEDOT:PSS with glycerol and sorbitol treatment.

This paper presents a simple, fast, and inexpensive method for the large-scale fabrication of polymer-based humidity sensors on glass substrates. The nanoparticles were synthesized using laser ablation, this is an environmentally friendly method for fabricating metal nanoparticles and provides a unique tool for nanofabrication. In this work, humidity sensing material, poly(3,4 ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) along with different kinds of nanoparticles, Au and Ag, are employed to enhance the stability and sensitivity to humidity sensing. Based on the experimental results, the TEM images show the crystallinity of the nanoparticles, indicating alloying of the nanoparticles. Based on XRD, this result indicates that the amorphous structure of PEDOT:PSS is only slightly affected by mixing with nanoparticles. According to FE-SEM analysis, the formation of interconnected crystallites facilitates the charge transport mechanism in the polymer chains due to improved conduction paths. Has been Characterization of humidity sensors Using (LCR), study the effect of humidity on capacitance at different frequencies (100Hz, 1kHz, 10kHz, and 100kHz), and the response and recovery time characteristics. The results show excellent linear and active behavior of the capacitive humidity response. Ag, PEDOT, and Au NPs have a synergistic effect, exhibiting a more extended sensing range and better stability. This work shows a high-sensitivity and low-cost sensing material for different humidity sensor applications.

This paper presents a simple and effective method to fabricate water-soluble two-dimensional (2D) conductive poly(3,4-ethylenedioxythiophene):poly (sodium 4-styrenesulfonate) (PEDOT:PSS) nanosheets. Linear PSS is water-soluble and exhibits a quasi 1D structure in the dilute solution. Addition of 3,4-ethylenedioxythiophene (EDOT) monomers into acidic solutions would form 2D molecular complexes due to charge attraction. In situ polymerization of the ethylenedioxythiophene monomers produces 2D poly EDOT nanosheets. Both transmission electron microscopy and atomic force microscopy characterizations have confirmed the 2D polymeric nanosheets. Further Fourier transform infrared (FTIR) characterization also validated that the 2D nanosheet is composed of EDOT-based units and Raman spectroscopy indicated the strong interactions between ethylenedioxythiophene units in the 2D nanostructures. The electrical conductivity is measured to as high as 551.58 S/m for the thin film of as-produced 2D PEDOT:PSS nanosheets.

A practical sensor based on a glassy carbon electrode (GCE) modified with exfoliated graphene (GR) and poly (3,4-ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT:PSS) was prepared to determine L-tryptophan (L-Trp) via differential pulse voltammetry (DPV). Optical microscopy was utilized to characterize the surface morphology of the composite electrode. Electrochemical behaviors of the composite electrodes were carried out via cyclic voltammetry (CV). According to DPV results, there are linear relationships between the peak currents and the concentrations in the ranges of 0.1–100$\mu$molL${}^{-1}$ and 100–1000$\mu$molL${}^{-1}$ for L-Trp, with the detection limit of 0.015$\mu$molL${}^{-1}$ for L-Trp. Moreover, the modified electrode can eliminate the interference effects of Ca${}^{2+}$, Mg${}^{2+}$, K${}^{+}$, Na${}^{+}$, L-tyrosine and ascorbic acid, which exhibit excellent stability and reproducibility.

There is a growing interest in the change in the conductivity of the conductive polymer Poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonate) (PEDOT:PSS). However, there is lack of research on the change in the conductivity of organic-based conductive materials compared to inorganic-based conductive materials. This study looks at the change in the conductivity of PEDOT:PSS with dimethyl sulfoxide (DMSO) mixing. The 4-point probe was used for observing the sheet-resistance changes. The relational degree of doping of PEDOT:PSS was confirmed by use of the Raman spectra. From the study, it was confirmed that PSS decreased in the UV-Vis spectra. We also observed that topology changes with the amount of DMSO through the AFM image. From the whole mobility and these analyses, we propose a reasonable conductive improvement mechanism of PEDOT:PSS.

This study describes an easy and cheap inkjet printing method for producing a paper-based gas sensor consisting of a composite film made of graphene oxide and poly(3,4-ethylenedioxythiophene) and poly(styrenesulfonate) (PEDOT:PSS). A glossy paper substrate is an inkjet printed with ink made by dispersing graphene oxide in a PEDOT:PSS conducting polymer solution to test its ability to detect ammonia (${\text{NH}}_3)$ at ambient temperature. The presence of few-layer graphene oxide in the PEDOT:PSS copolymer and the existence of $\pi$–$\pi$ interactions between graphene oxide and PEDOT:PSS are confirmed by Fourier transform infrared spectroscopy, UV–Visible spectrophotometer, and X-ray diffraction. In a small concentration range of 1–100 ppm at ambient temperature, the ink-jet printed graphene oxide-PEDOT:PSS gas sensor displays strong responsiveness and good selectivity to NH₃. The study found that ${\mathrm{\text{NH}}}_4$ is a strong donor in the ammonia gas produced by a bubble system of ammonia water, with ${\mathrm{\text{NH}}}_4$ molecules being ideal candidates for molecular doping of graphene. The ${\mathrm{\text{H}}}_2\mathrm{\text{O}}$ molecule can facilitate quick desorption by converting ${\mathrm{\text{NH}}}_3$ to ${\mathrm{\text{NH}}}_4$. The interaction between graphene oxide and ${\mathrm{\text{NH}}}_3$ molecules is weak. The attained gas-sensing performance may be attributed to the increased specific surface area of graphene oxide and enhanced interactions between the sensing film and ${\mathrm{\text{NH}}}_3$ molecules via $\pi$ and lone pair electron network. The ${\mathrm{\text{NH}}}_3$-sensing mechanisms of the flexible printed gas sensor are based on the competitive interaction of ammonia on the sensor, adsorption and dissociate ionization on the sensor surface.