Electrochromic polymers colors

Amb, C. M. Dyer, A. L. Reynolds,. R., Navigating the color palette of solution-processable electrochromic polymers. Chem. Mater 2010, 23, 397-415. 

Gaupp, C.L., Welsh, D.M., Ranh, R.D., and Reynolds, J.R. 2002. Composite coloration efficiency measurements of electrochromic polymers based on 3,4-alkylenedioxythio-phenes. Chemistry of Materials 14, 3964—3970. 

Another rather special strategy to obtain electrochromic polymers with unexpected performance is covalently connecting electrochromic units to the conjugated polymer backbone. Lee and coworkers have reported a new polymer 119 (Fig. 2.7B) thatis aPEDOT derivative containing a pendant viologen (Ko et al, 2004). Electrochemical and spec-troelectrochemical studies showed that this polymer had four colored oxidation states. 

Wu, C.G., Lu, M.I., Chang, S.J.,Wei, C.S., 2007. A Solution-processable high-coloration-efficiency low-switching-voltage electrochromic polymer based onpolycyclopentadithiophene. Adv. Eunct. Mater. 17,1063-1070. 

Alamer, F.A., Otley, M.T., Ding, Y., Sotzing, GA., 2013. Solid-state high-throughput screening for color tuning of electrochromic polymers. Adv. Mater. 25,6256-6260. 

Bhuvana, T, Kim, B., Yang, X., Shin, H., Kim, E., 2013. Reversible fuU-color generation with patterned yellow electrochromic polymers. Angew. Chem. Int. Ed. 52,1180-1184. 

Gunbas, G.E., Durmus, A., Toppare, L., 2008. Could green be greener Novel donor-acceptor-type electrochromic polymers towards excellent neutral green materials with exceptional transmissive oxidized states for completion of RGB color space. Adv. Mater. 20,691-695. 

Gaupp C. L., Welsh D. M., and Reynolds J. R, Poly[ProDOT-Et2] a high-contrast, high-coloration efficiency electrochromic polymer, Macromol. Rapid Commun., 2002,23,885-889. 

Du Bois, C.J., et al. 2001. Multi-colored electrochromic polymers based on BEDOT-pyridines. Synth Met 119 321. 

Electrochromic polymers have also been prepared by electropolymerization of a precursor involving a median core substituted by two EDOT units. Modification of the nature of the median core (vinyl, thienyl, phenyl, furan, etc.) allows for the tuning of the bandgap of the polymers and thus the color of the oxidized and reduced state [293]. 

Reeves, B.D., B.C. Thompson, K.A. Abboud, B.E. Smart, and J.R. Reynolds. 2002. Dual cathodically and anodically coloring electrochromic polymer based on a spiro bipropylenedioxythiophene [poly(spiroBiProDOT)]. Adv Mater 14 717-719. 

This section focuses on the influence of structure of the repeat unit on the colors available in the neutral, oxidized, and in some instances the reduced forms for the various families of electrochromic polymers. The section also covers the electrochromism of parent polymers and the result that the addition of substituents with a variety of functionalities has on the electrochromism. 

The combination of various device platforms, along with electrochromic polymers available in colors that span the entire range of the visible spectrum and beyond, allows the construction of displays that can be tailored to fit most needs in real applications. While these devices have shown enhanced performance in colors available, optical memory, and low power consumption as compared to devices constructed of other electrochromic materials, there are still drawbacks to be addressed. 

Witker, D. and J.R. Reynolds. 2005. Soluble variable color carbazole-containing electrochromic polymers. Macromolecules 38 7636-7644. 

Aubert, R.-H., A.A. Argun, A. Cirpan, D.B. Tanner, and J.R. Reynolds. 2004. Microporous patterned electrodes for color-matched electrochromic polymer displays. Chem Mater 16 2386-2393. 

Thiophene-based Electrochromic Materials 777 Table 20.2 Electrochromic polymers with colors in both doped and undoped states... 

Polythiophenes with P-alkyl substituents including more than three carbon atoms are commonly soluble in organic solvents. Recently, electrochromic polymers such as poly(thiophene-3-acetic acid) and its copolymer with polythiophene were prepared. The electrochromic properties of these materials were studied by observing a color change from red to black during the potential sweep with a stability for 264 cycles, establishing a high electrochromic efficiency of up to 242 cm C at 750 nm [65],... 

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