Effect of monomer concentration and substrate resistance on redox behaviour of polyaniline films

Template Free Electrochemical Synthesis of Highly Crystalline Polyaniline Nanopetals, Nanocrystals and Their Field Electron Emission Investigations

“…The peaks around 0.1 V are due to formation of radical cation of PANI, which initiate its deposition on the electrode surface, while the peak around 0.48 V is attributed to formation benzoquinone and hydroquinone coupling during PANI growth. 27 For the higher scan rates 0.02 ESI-Figure † 1(c) and 0.05 V/s ESI-Figure † 1(d) the shoulder peaks are observed to diminish in the 1 st cycle, and finally for the scan rate 0.5 V/s ESI-Figure † 1(e)) the current increases continuously in the 1 st cycle without exhibiting any well 'defined' peaks. But in the 10 th cycle, well resolved anodic and cathodic peaks are observed for these scan rates.…”

“…The CV curves clearly indicate that the PANI films exhibit redox behavior, similar to the earlier reports. 26,27 The peaks at 0.1 V and 0.4 V are attributed to the formation of passive layer followed by the oxidation of aniline monomer on electrode surface. The formation of a passive layer on reactive substrates during electrochemical synthesis in presence of aqueous electrolyte has been exemplified by various researchers.…”

Studies of electrochemically deposited poly(N-methyl aniline) films

“…These results can be explained by two di †erent polymerization mechanisms operating at lower and higher monomer concentrations as reported earlier. 23 Another signiÐcant parameter of interest is the inÑu-ence of the surface resistance of the electrode on the cyclic voltammetric features of poly(N-methyl aniline) Ðlms. At lower monomer concentration of 0É2 M the cyclic voltammograms of the Ðlms deposited on the electrode with surface resistance (Fig.…”

Electrochemical preparation and characterisation of Poly(Luminol–Aniline) films

“…Peak B, which in the pure PAni films presents lower current density than peaks A and C (inset in Fig. 6), has been assigned to polyaniline degradation products [24,26,27] and may be consequence of the high anodic limit potential (E al = 0.950 V) and of the low aniline concentration used in the polymerisation. P(Lum-Ani) (1:20) and (1:60) films presents lower oxidation and reduction charges and higher current densities of the intermediary peak B (at about 0.450 V) than observed for PAni (0:20) and (0:60) films.…”

“…The peak at more cathodic potentials has been attributed to the conversion of the fully reduced and insulating leucoemeraldine in the semi-oxidised and conducting emeraldine form and the anodic peak to the conversion of the electronically conducting emeraldine in the fully oxidised and insulating pernigraniline form. An intermediary redox process has been assigned to degradation products of PAni such as benzoquinone/hydroquinone units, which is dependent on the electrosynthesis conditions, such as anodic potential/synthesis charge and monomer concentration [24,26,27].…”