Cyclic voltammetry poly thiophene

The electropolymerization of ferrocene/thiophene conjugates [65] was conducted by oxidation on a Pt electrode and led to the deposition of a monolayer of poly (thiophene). The electropolymerization was performed from several solution systems, such as tetrabutylammonium hexafluorophosphate/acetonitrile and lithium perchlorate/acetonitrile, at a concentration of 0.1 M. Constant potential experiments (+ 2.0 V) for a definite time were used to effect polymerization. Polymerization was also attempted using cyclic voltammetry (repeatedly sweeping from 0.0 to + 2.5 V) and pulse potential (potential stepped from 0.0 to 2.0 V and back to 0.0 V). 

In further studies, the self-doping mechanism of these polymers was verified by cyclic voltammetry, pH measurements and atomic absorption spectroscopy [17,20]. The cyclic voltammograms of the sodium salt and acid forms of poly(3-thiophene butanesulfonate) cast films are shown in... 

In reality, there is no absolute proof in favour of either of these mechanisms, but it appears to be generally agreed that cationic coupling is the most important mechanism for the formation of poly(/ -phenylene). It must be emphasized that in the case of the electropolymerization of pyrole and thiophene, which are electropolymerized in much the same way as benzene, the radical-cationic coupling mechanism was proven from kinetic results deduced from ultra-fast cyclic voltammetry experiments [153]. Isotopic studies... 

Poly(naphtho[2,3-r]thiophene-fl//-bithiophene) (36) was also prepared by Cava and coworkers [77,78] electrochemically (Bu4N PF6 /CH2Cl2) as shown in Scheme 11. The polymer was gray in the neutral form and became blue when oxidized. Neutral 36 showed a broad absorption maximum at 476 nm with a shoulder in the near-infrared at 1240 nm. The band edge of this shoulder was at 1900 nm, and this provided a band gap of 0.65 eV. The electrical conductivity of an electrochemically doped film of 36 was 2 x 10 S/cm and that of a FeCL-doped film was 1 x 10 S/cm. Cyclic voltammetry of a film of polymer 36 on a platinum disk electrode showed two oxidation waves at 0.57 and 0.87 V (SCE) [77,78]. 

After the report of poly[2.2]metacyclophane 3 described above, there were no reports on the synthesis of cyclophane-based ju-stacked polymers for over 15 years. In 2001 and 2002, polymerizations of thiophene-substituted [2.2]paracyclophanes were reported independently by two research groups [13-16]. Both groups synthesized jc-stacked polymers by electrochemical polymerization using cyclic voltammetry. For example, Audebert and coworkers reported that the electrochemical polymerization of monomer 5 deposited jr-stacked polymer 6 on a glassy carbon or indium-tin oxide electrode (Scheme 2) [13, 14]. 

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