Polyethylenes PEDOT

Fig. 4.14 (a) Optical transmittance of graphene on a polyethylene terephthalate (PET) flexible substrate [19]. Optical and electrical data for PEDOT PSS-based composites with SWCNT (b) transmittance at 550 nm, (c) sheet resistance, (d) DC conductivity and (e) ratio of DC to optical conductivity. 

The first conducting polymer was trans-polyacetylene which was doped with bromine and was produced at 1970s. Soon other conjugated polymers such as poly (p-phenylene), polypyrrole (PPy), polyethylene dioxythiophene (PEDOT) and polyaniline (PANi) and their derivatives which are stable and processable were synthesized. The molecular structures of a few ICPs are shown in Figurel. 

CVD = chemical vapor deposition DH = double heterostructure H = homojunction device ITO = indium tin oxide LEDs = light emitting diodes LPE = liquid phase epitaxy MBE = molecular beam epitaxy MOCVD = metal organic chemical vapor deposition PPV = p-phenylenevinyl-ene PEDOT = polyethylene dioxythiophene TFEL = Thin film electroluminescent VPE = vapor phase epitaxy. 

In this contribution, we discuss the impact that CuPc C6o absorber composition and its preparation temperature has on device PV parameters as well as on electrical and transport properties. ITO/3,4-polyethylene-dioxythiophene polystyrenesulfonate (PEDOT PSS)/CuPc C6o/Mg/Ag OSCs are investigated. 

The two electrons transferred from TDAE to PEDOT-PSS are expected to undope the conjugated polymer chains. Since TDAE diffuses into PEDOT-PSS, long exposures to the electron donor induce changes in the optical properties of the polymer film. Optical absorption experiments on 200 nm thick PEDOT-PSS films coated onto a transparent polyethylene terephthalate (PET) substrate. The pol5mier film was exposed to the TDAE vapor in an inert nitrogen atmosphere and shows the difference in absorption spectrum between a film exposed to TDAE and the pristine PEDOT-PSS layer (Figs. 3.10 and 3.11). The modification of the optical properties and the sheet resistance of the pol5mier layer were recorded versus exposure time. The two absorption features at 550 nm and... 

However, the production of all-organic fibers from ICPs is still complicated and expensive. Several attempts have been made to obtain conductive fibers from ICPs such as polyaniline, PEDOT PSS, and pure PEDOT with conductivity values from 150 to 250 S/cm [22,23]. However, due to poor mechanical strength, microscale size, a low production rate, brittleness, and difficult processing, useful commercial applications are stiU limited. On the other hand, combination of other textile materials with ICPs could enhance their application areas. It could be done in two ways, either by mixing ICPs with insulating polymers such as polypropylene, polyethylene, and polystyrene, or by coating conventional textiles with ICPs. The coating method is explained in the next section. 

In the UK, researchers at Cambridge University have devised a method of growing vertical carbon nanotubes on a flexible plastic substrate which gives scope for further research into potential applications especially where flexibility is a key element of the product design. At Sheffield University the research project involves the dispersion of nano-sized droplets of PEDOT (or other conducting polymers) into a polyethylene oxide polymer electrolyte matrix. Together with a suitable redox couple, where oxidation and reduction are considered together as complementary processes, it is possible to produce efficient, switchable windows for microwaves. 

Souze et al. have fabricated the solid electrolyte-based supercapacitor based on SWCNTs/PANI on polyethylene terephthalate-PET substrates. They have used H2SO4-PVA gel electrolyte and measured the pseudocapacitive properties and estimated the coulometric specific capacitance of 76.7 F cm [87]. The poly (3,4-ethylenedioxypyrrole) and PEDOT wrapped Sb2S3 nanorods were synthesized hydrothermally by Reddy et al. [88] and 1008 F/g specific capacitance, 504 W/kg power density, and 88 % capacitance retention over 1000 cycles were estimated in the fabricated supercapacitor. Further, the supercapacitor was fabricated using semisolid electrolyte using PMMA in ionic liquid. 

The aqueous dispersion of PEDOTiPSS has a surface tension of approximately 65 to 71 mN/m depending on the ratio of PEDOT to PSS. Such a surface tension is too high to wet hydrophobic surfaces such as plastic substrates like polyethylene terephthalate (PET), polycarbonate (PC), or polyethylene (PE) with aqueous PEDOT PSS dispersion. 

Chemical structures of viologen side group modified PEDOT (PolyViolEDOT), polyethylene-dioxythiophene (PEDOT), and polymeric viologens (PolyViol). 

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