ChemInform Abstract: ELECTROCHROMISM OF ORGANIC COMPOUNDS. II. SPECTRAL‐ELECTROCHEMICAL STUDY OF A A SYSTEM BASED ON METHYLVIOLOGEN AND 5,10‐DIHYDRO‐5,10‐DIMETHYLPHENAZINE

The influences of operating voltage and cell gap on the performance of a solution-phase electrochromic device containing HV and TMPD

“…Complementary electrochromic devices (ECDs) [1][2][3][4] based on viologens were first studied in the 1970s and can provide high transmittance changes (of over 80%) and fast responses. The response times reported were on the orders of 10 -50 ms for darkening and 10 -100 ms for bleaching [1,4].…”

“…Viologen is the common name for 1,1V -disubstituted-4,4V-bipyridinium salt since the radical cation of 1,1V-dimethyl-4,4V -bipyridinium (methyl viologen; MV) found by Michaelis and Hill [5] is of violet color. In addition to being used in ECDs [1][2][3][4]6], applications of viologens in herbicides [7], electron mediators [8], and catalysts [9] have also been demonstrated. Among viologens, 1,1V-diheptyl-4,4V -bipyridinium (heptyl viologen; HV) is usually used for electrochromic applications because its radical cation salt (denoted as HV Á + X À , in which X À is the counterion) can form an insoluble violet film on an electrode surface when 0167-2738/$ -see front matter D 2003 Elsevier B.V. All rights reserved.…”

True Blue Through Oxidation—A Thiaazulenic Heterophenoquinone as Electrochrome

“…[4] Generally, electrochromes are composed of inorganic metal oxides such as WO 3 , [5] of polyarylene- [6] and polyaniline-type [7] polymers, or of small molecules such as viologens, [8] but also of electroactive quinones [9] and phenazines. [10] Electrochromicd evices are operated in solution (or gel) phases (type I), in solution/solid (type II) and entirely in the solid state (type III, metal oxides, conjugatedp olymers). [11] Small molecule electrochromes are either of type Io r II, and either anodic [12] or cathodic [13] coloring can be achieved.…”