Electropolymerization carbazole

Composites of polypyrrole and poly(vinyl chloride) have been prepared by several groups (64-67). Polythiophene-poly(vinyl chloride) composites have also been prepared (68). The electropolymerization of pyrrole on poly(vinyl chloride)-coated electrodes yielded composites with mechanical properties (tensile strength, percent elongation at break, percent elongation at yield) similar to poly(vinyl chloride) (65) but with a conductivity of 5-50 S/cm, which is only slightly inferior to polypyrrole (30-60 S/cm) prepared under similar conditions. In addition, the environmental stability was enhanced. Morphological studies (69) showed that the polypyrrole was not uniformly distributed in the film and had polypyrrole-rich layers next to the electrode. Similarly, poly(vinyl alcohol) (70) poly[(vinylidine chloride)-co-(trifluoroethylene)] (69) and brominated poly(vinyl carbazole) (71) have been used as the matrix polymers. The chemical polymerization of pyrrole in a poly(vinyl alcohol) matrix by ferric chloride and potassium ferricyanide also yielded conducting composites with conductivities of 10 S/cm (72-74). 

G. Inzelt. Formation and redox behaviour of poly carbazole prepared by electropolymerization of solid carbazole crystals immobilized on an electrode surface. J. Solid State Electrochem., 7(8) 503-510, August 2003. 

Differendy linked carbazole derivatives possessing selenophene and pyrene (the latter not covered in this review) moieties were electropoly-merized (14EA430). The electropolymerized polymers displayed unusual properties upon electrochemical doping suggesting their potential use as electroactive layers in electrochromic devices. A typical synthesis of 2,7-diselenophenylcarbazole is shown below. 

For the electropolymerization of aniline it is necessary to include a protonation step, as the polymer is protonated in the acid medium employed [13]. The foregoing mechanism shows that the growth of the polymer can be influenced by the kinetics of any of the steps in the process. Consider the cyclic voltammogram for the electrodeposition of polycarbazole shown in Fig. 1. Initially, the charge transfer controls the kinetics. After the first peak due to the oxidation of the carbazole monomer, a shoulder or hump may also be discerned at more positive potentials. This is the signature of a nucleation step. 

The direct electrochemistry of redox proteins such as ferredoxin and blue copper protein was studied. The additional effect of poly(L-lysine) on the redox behaviour of horse heart cyt c at functional electrodes has been reported Electropolymerized films such as PAn undergo redox reactions producing a colour change. This is described in Sect. 5.2. The anodic oxidation of poly(iV-vinylcarbazole) films was shown to involve initially the cross-linking of the polymer chains by oxidation of the carbazole moieties and dimerization of the resulting pendant carbazole cation radicals The resulting dimeric carbazole unit is more easily oxidized than the monomer and undergoes a further (reversible) two-electron oxidation. 

There was an attempt to construct a BHJ SC with controlled morphology of an active layer using a layer-by-layer assembling with consecutive electropolymerization of the resulting layers to form a covalently linked D-A active material of precisely controllable thickness [116]. Electropolymerization was performed under potentiodynamic conditions by coupling IV-alkylcarbazole moieties of both D and A units. A photoactive layer was composed of three carbazol-derivatized components, i.e., [Ceolfullerene, ZnP, and oligofluorene derivatives (Scheme 53). The PCE of... 

Many other aromatic systems can be similarly electropolymerized, including thiophene, furan, carbazole, azulene, indole, aniline, phenol and thiophenol among others. 

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