TY  - JOUR
A1  - Dimitriev, O. P.
A1  - Smertenko, P. S.
A1  - Stiller, Burkhard
A1  - Brehmer, Ludwig
T1  - Polyaniline-transition metal salt complexes: insight into formation mechanisms
N2  - Two basic morphologies of emeraldine base of polyaniline-transition metal salt complex films cast from N- methylpyrrolidinone solutions are described. The first morphology consists of grains and the other consists of loose aggregates, respectively. The correlation of the film morphology with formation of precipitate in the complex solution, kinetics of solvent evaporation from the cast film, amount of solvent entrapped in the film, film conductivity, and IR absorption spectra is shown. Two different mechanisms of the complex formation as a result of competition in the polymer- inorganic salt-solvent trio interactions are discussed; the first mechanism results in folding of macromolecules into compact coils being then a core of grains in the complex films, and the second mechanism leads to blending of the polymer chains with solvent giving rise to formation of loose aggregates. (c) 2005 Elsevier B.V. All rights reserved
Y1  - 2005
SN  - 0379-6779
ER  - 
TY  - JOUR
A1  - Smertenko, P. S.
A1  - Dimitriev, O. P.
A1  - Schrader, Sigurd
A1  - Brehmer, Ludwig
T1  - Doping of polyaniline by transition metal salts : current-voltage characteristics of the ITO/polymer film/metal heterostructures
N2  - Films of emeraldine base of polyaniline (PAni) doped by various transition metal salts have been prepared, and current-voltage characteristics of the indium-tin oxide (ITO)/PAni film/metal electrode heterostructures were investigated. It was found that the electrical characteristics of the heterostructures are greatly affected by the dopant used and the metal electrode used. Different dopants resulted in different current anomalies with asymmetric current-voltage characteristics. Depending on the dopant used, the exponential and power law of the current behavior can be distinguished. Depending on the metal electrode used, two different regimes of current passing have been found at low applied voltages, namely, a nearly ohmic regime for the indium electrode, and a diode regime for the aluminum electrode. The diode regime was found to accompany by a positive charge accumulation in the film near the film/metal interface, which creates a built-in potential in the film. The amount of positive charges accumulated at the interface and therefore the value of the built-in potential can be reversibly increased or reduced by successive runs of the applied voltage in the forward or reverse direction, respectively. (C) 2004 Elsevier B.V. All rights reserved
Y1  - 2004
SN  - 0379-6779
ER  -