Spectroelectrochemical study of the copper(II) transfer assisted by 6,7-dimethyl-2,3-di(2-pyridyl)quinoxaline at the water vertical bar 1,2-dichloroethane interface

• Type: Article in International Scientific Journal
• Date: 1998

Authors

Tomaszewski, L (Author) Other; Ding, ZF (Author) Other; Fermin, DJ (Author) Other; Cacote, HM (Author) Other; Pereira, CM (Author) FCUP; Silva, F (Author) FCUP; Girault, HH (Author) Other

Journal

The Journal is awaiting validation by the Administrative Services.

Title: JOURNAL OF ELECTROANALYTICAL CHEMISTRY

Vol. 453

Pages: 171-177

ISSN: 0022-0728

Indexing

ISI Web of Knowledge - 30 Citations

Scopus - 32 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-001-7A0

DOI: 10.1016/s0022-0728(98)00183-1

Abstract (EN): The assisted transfer of Cu(II) by interfacial complexation with 6,7-dimethyl-2,3-di(2-pyridyl)quinoxaline (DMDPQ) is studied at the polarised water\1,2-dichloroethane junction. Thermodynamic and kinetic aspects were addressed by cyclic voltammetry and in situ spectrophotometric measurements. The dependence of the half wave transfer potential on the ligand concentration suggests that the equilibrium is effectively displaced towards a 1:3 (metal:ligand) stoichiometry, with an association constant of log beta(3)degrees = 26.0. Visible spectra recorded by reflection from the aqueous phase showed the presence of two absorption bands at 400 and 500 nm associated with the Cu(II) complex. Chronoabsorptometric studies in the presence of a ligand excess suggest that the assisted transfer kinetics are effectively controlled by the diffusion of the metal ion to the interface.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7