Kawata, Tsutomu; Yamamoto, Motokazu; Yamana, Masao; Tajima, Moritaka; Nakano, Tomoyasu published an article in 1975, the title of the article was Characteristics of viologen derivatives for electrochromic display.Recommanded Product: 1,1′-Dipropyl-[4,4′-bipyridine]-1,1′-diium bromide And the article contains the following content:
The polarog. half-wave potentials (E1/2, in aqueous solutions with pH 3.29 at 25°) and the absorption spectra (at λ = 250-700 nm) in various media (aqueous solution, MeOH, glycerin) were determined to characterize the electrochromic behavior of the viologen derivatives X-RN+C5H4-C5H4N+RX- [= Viol] (R = Pr, C6H13, or C7H15 for X = Br; X = Cl, Br, or I for R = PhCH2). Two polarog. waves were observed for each derivative: the 1st E1/2 [= 0.568-0.710 V vs. SCE] was attributed to the reduction, dication of Viol (I, colorless) + e- ⇄ radical cation (II, colored); and the 2nd E1/2 [= 0.775-0.965 V] was attributed to II + e- ⇄ biradical (III, colored). The E1/2 values were smaller for the PhCH2 derivatives than for the alkyl derivatives For R = PhCH2, the observed absorption maximum were at λ (in nm) ≈ 260 for I, ≈ 260, 400, and 630 for II, and ≈ 380 for III. With a viologen derivative in an electrochromic display device (having a transparent SnO2 cathode and a Pt anode), the writing time decreased with increasing applied voltage, and was ∼0.4-0.8 sec for obtaining a transmittance of 80%. An applied voltage greater than the 2nd E1/2 caused the color to change from purple to yellow; on open circuit, the color changed back to purple. The experimental process involved the reaction of 1,1′-Dipropyl-[4,4′-bipyridine]-1,1′-diium bromide(cas: 52243-87-5).Recommanded Product: 1,1′-Dipropyl-[4,4′-bipyridine]-1,1′-diium bromide
The Article related to viologen derivative polarog optical absorption, electrochromic display viologen derivative, Electric Phenomena: Other Devices and other aspects.Recommanded Product: 1,1′-Dipropyl-[4,4′-bipyridine]-1,1′-diium bromide