Electrochemical characterization of Co(II) and Pd(II) phthalocyanines carrying diethoxymalonyl and carboxymethyl substituents |
| |
Authors: | A Koca H A Dinçer M B Koçak A Gül |
| |
Institution: | 1. Marmara University, 34722, G?ztepe, Istanbul, Turkey 2. Istanbul Technical Faculty, 80626, Maslak, Istanbul, Turkey
|
| |
Abstract: | In this study, electrochemical behaviors of Co(II) and Pd(II) phthalocyanines carrying tetrakisdiethoxymalonyl and Pd(II)
phthalocyanine carrying tetrakiscarboxymethyl substituents at the peripheral positions are investigated by cyclic voltammetry
and applied potential chronocoulometry techniques. Cyclic voltammetric studies show that, while Pd(II) phthalocyanines carrying
diethoxymalonyl and carboxymethyl substituents give up to three common phthalocyanine ring reductions, Co(II) phthalocyanine
carrying diethoxymalonyl substituents gives a metal-centered oxidation and a metal-centered reduction and three ligand-centered
reduction and a ligand-centered oxidation processes. First reduction processes of both the PdPc complexes have shoulders.
This different voltammetric behaviors of Pd(II) phthalocyanines carrying carboxymethyl and diethoxymalonyl substituents results
from interaction of this distinctive substituents with the phthalocyanine ring π electron system and interaction with the
different solvent systems. Observation of the splitting of the first reduction process of Pd(II) phthalocyanines carrying
diethoxymalonyl and carboxymethyl substituents suggests the aggregation of the complex. Very small diffusion coefficient of
the complexes with respect to Co(II) phthalocyanine also confirms the existence of the aggregation of the complex during the
electrochemical studies. Effects of the substituents and the solvent media are clearly observed from the differences of the
voltammograms of Pd(II) phthalocyanines carrying diethoxymalonyl and carboxymethyl substituents in DMSO and THF solvent media,
respectively.
Published in Russian in Elektrokhimiya, 2006, Vol. 42, No. 1, pp. 36–43.
The text was submitted by the authors in English. |
| |
Keywords: | electrochemistry cyclic voltammetry aggregation cobalt palladium phthalocyanines metal complexes |
本文献已被 SpringerLink 等数据库收录! |
|