Wyniki wyszukiwania - BazTech

Ograniczanie wyników

1 Advances in Materials Science

1 2007

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Influence of aliphatic organic acids on the properties of PPy films electrodeposited on aluminum surfaces

Liu A.S., Oliveira M.A.S.

Advances in Materials Science

2007

Vol. 7, nr 2(12)

223-235

Polypyrrole (PPy) films were galvanostatically deposited on 99.9 wt.% aluminum e1ectrodes from aqueous solutions containing each carboxylic acid: tartaric, oxalic or citric. The thickness of the PPy films was measured by Perfilometry. It was observed that PPy films electrodeposited from oxalic acid medium were thicker than those electrodeposited from the electrolytes containing the other twa organic acids. This observation was a consequence of the nature of the oxide layer produced during the electrodeposition of PPy. More compact oxide layers difficult the electron-transfer reactions and consequently the pyrrole oxidation. The morphology and roughness of the aluminum surfaces coated with the polymeric films were analyzed by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM), respectively. It was observed that the films deposited from tartaric acid medium presented higher homogeneity and smaller roughness than those formed in oxalic and citric acid media. Furthennore, the corrosion protection of aluminum surfaces by PPy films was also investigated by potentiodynamic polarization experiments. These experiments demonstrated that the aliphatic acids also influence the corrosion protection afforded by the PPy films on aluminum surfaces.