3.4- Ethylene-dioxythiophene

Bhandari, S. Deepa, M. Srivastava, A. K. Joshi, A. G. Kant, R., Poly (3, 4-Ethylene-dioxythiophene)- multiwalled carbon nanotube composite films structure-directed amplified electrochromic response and improved redox activity./. Phys. Chem. B2009,113, 9416-9428. 

After Little s proposal, many researchers have pursued such an exciting system in vain. Even metallic behavior was rarely seen in doped organic polymers, gels, and actuators. As mentioned in Sect. 3.4.4, MCso with linearly polymerized Ceo" exhibited one-dimensional (M = Rb, Cs) or three-dimensional (M = K) metallic behavior [144]. Recently a doped poly aniline was reported to exhibit a metallic temperature dependence for a crystalline polymer chemical oxidation of monomers grew crystallite polyaniline [329] early doping studies on polypyrrole (PFg) and poly(3,4-ethylene-dioxythiophene)X (X = PFg, BF4, and CF3SO3) prepared by electrooxidation at low temperatures also showed a metallic temperature dependence below 10-20 K (Scheme 16) [330, 331]. 

Scheme 16 Chemical stmctures of pyrrole and 3,4-ethylene-dioxythiophene...

Huang J. S., Miller P. F., Wilson J. S., de Mello A. J., de Mello J. C. and Bradley D. D. C. (2005), Investigation of the effects of doping and post-deposition treatments on the conductivity, morphology, and work function of poly (3,4-ethylene-dioxythiophene)/poly(styrenesulfonate) films , Adv. Funct. Mat. 15, 290-296. 

Ho KC, Yeh WM, Tung TS, Liao JY (2005) Amperometric detection of morphine based on poly(3,4-ethylene dioxythiophene) immobilized molecularly imprinted polymer particles prepared by precipitation polymerization. Anal Chim Act 542(1 ) 90—96... 

Before ending this section, the current density-voltage-luminance characteristics of two PLEDs using Ag/Ca (solid symbol) and Ag/Al/CsF (open symbol) as a cathode, respectively, with 40 nm of poly(3,4-ethylene dioxythiophene) (PEDOT) polystyrene sulfonate) (PSS) as a polymer anode and 100 nm of F8BTas a green-emitting layer are depicted in Fig. 5.16. The thickness of the Ca, CsF, A1 and Ag layers is 50, 5, 80 and 100 nm, respectively. The Al/CsF instead of Cs was used as the cathode since the role of A1 on CsF is known to release Cs into the polymer [80], It can be seen that the Ca device shows much larger current density than the CsF/Al device, in contrast to the common belief that the lower work function of... 

Zhn, Z.-T. et al., A simple poly(3,4-ethylene dioxythiophene)/poly(styrene snlfonic acid) transistor for glncose sensing at nentral pH, Chem. Commun., 13, 1556, 2004. Zhn, Z-T. et al., Hnmidity sensors based on pentacene thin-fihn transistors, Appl. Phys. Lett., 81, 4643, 2002. 

In a recent pubHcation, Alivisatos and co-workers reported the making of hybrid nanorods-polymer solar cells and their properties [122]. These solar cells were made by spin casting of a solution of both poly(3-hexylthiophene) (hole acceptor) and CdSe nanorods (electron acceptor) onto indium tin oxide glass substrates coated with poly(ethylene dioxythiophene) doped with polystyrene sulfonic acid and aluminum as a top contact. Nanorods have been used in composites so as to improve the carrier mobiHty. Indeed, the latter can be high for some inorganic semiconductors, but it is typically extremely low for conjugated polymers [123]. The use of the nanorods suppHes an interface for the charge transfer as well as a direct path for electrical transport. Also, because of their anisotropy, self-assembly of these nanorods is observed by electron microscopy. It shows... 

The LBL, in-situ self-assembled LBL films of PPy, PANI, polyhexylthiophene, and poly(ethylene dioxythiophene) (PEDT) and hybrid cross-linked nanocomposite thin film for NOx gas sensing were fabricated [68,70,101-106] for NO2 sensing application. Layered films of conducting polymer nanocomposite films were fabricated similar to the one explained in Sections 2.2.1 and 2.2.2. 

Brown, T. M. Kim, J. S. Friend, R. H. Cacialli, R Daik, R. and Feast, W. J. 1999. Built-in field electroabsorption spectroscopy of polymer light-emitting diodes incorporating a doped poly(3,4-ethylene dioxythiophene) hole injection layer. Appl. Phys. Lett. 75 1679-1681. 

The surface of ITO can also be modified by deposition of a thin layer of various hole-injection materials (HIM), such as copper phthalocya-nine (CuPc), poly(3,4-ethylene dioxythiophene) (PEDOT), organosilane (CH30)3-Si-C3H7NH2, and many others. Use of an HIM between ITO and the HTL allows for achieving significant improvements in device stability and efficiency. 

Polythiophene derivates are polymers of great interest, widely used in organic electronics. Thus, the utilization of polythiophene nanofibers could open the path to the development of nanostructured organic electronics with a high surface area for a range of applications. El-Aufy, in his PhD thesis, studied poly(3,4-ethylene dioxythiophene)/ poly(styrenesulfonate) PEDOT/PSS nanofibers and nanocomposites using PAN as a... 

A. K. El-Aufy, PhD Thesis, Nanofibers and Nanocomposites Poly(3,4-Ethylene Dioxythiophene) / Poly (Styrene Sulfonate) by Electrospinning, Drexel University, Philadelphia PA (2004). 

K. Lota, V. Khomenko, and E. Frackoviak, Capacitance properties of poly(3,4-ethylene dioxythiophene)/carbon nanotubes composites, J. Phys. Chem. Solids, 65, 295-301 (2004). 

I. Baltog, M. Baibarac, S. Lefirant, and P. Gomez Romero, SERS studies on poly(3,4-ethylene dioxythiophene)/SWNTs composites and their application to rechargeable lithium batteries, J. Nanosci. Nanotech., 9, 6204—6209 (2009). 

Murugan et al. reported on the intercalation of electrically conductive poly(3,4-ethylene dioxythiophene) (PEDOT) into crystalline V2O5. PEDOT is a stable, environmentally friendly polymer with potential applications in supercapacitors and lithium ion batteries. PEDOT was encapsulated into V2O5 by treatment of the latter with the monomer (3,4-ethylene dioxythiophene). The reaction is essentially an in situ... 

S. BiaUozor and A. Kupniewska, Properties of electrrxles modified with poly(3,4-ethylene-dioxythiophene) and Pt particles - Part II, Bull. Electrochem., 20, 241-246 (2004). 

F. Vidal, J.F. Popp, C. Plesse, C. Chevrot, and D. Teyssie, Feasibility of conducting semi-interpenetrating networks based on a poly(ethylene oxide) network and poly(3,4-ethylene-dioxythiophene) in actuator design, J. Appl. Polym. Set, 90 (13), 3569-3577 (2003). 

Derivatives of PTh such as poly(ethylene dioxythiophene) (PEDOT) (Figure 18.3C), have been increasingly investigated for their superior electrochemical stabihty and ability to be tailored for altered functionality [36-39]. 

Figure 18.4 Schematic of conventional biological modification routes of CPs, shown for po y(3,4-ethylene dioxythiophene). The green molecule represents the biofunctional additive and the negatively charged purple molecule is the dopant anion (See colour Plate 10)...

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