title: Electrochemical and spectral studies of auto-assembled arrays of calix[4]arenequinhydrone charge-transfer complex on indium-tin oxide (ITO) glass.
abstract: A sensing materiel based on calix[4]arene molecules is electrochemically deposited on ITO electrode coated. A brown film was electrodeposited at a potential Eimp= -1.00 V versus SCE in acetonitrile solvent, however in dichloromethane solvent, a bluish film auto-assembled on the ITO electrode coated at a potential Eimp= -0.65 V versus SCE. Both films are subsequently analyzed by cyclic voltammetry and UV-Vis spectroscopy. This investigation shows that in acetonitrile solvent, the charge-transfer complex, calix[4]arenequinhydrone was formed in electrolytic solution and it was not self-assembled on the ITO electrode. The related UV-Vis spectrum shows a single absorption band towards a wavelength about 350 nm. The optical behaviour of the blue film shows two absorption bands: the first one appears on the first absorption band of the acceptor at 305 nm and the second one in the visible range at 502 nm. The band situated in the visible range correspond to a well-defined charge-transfer band indicating the presence of the charge-transfer complex, the calix[4]arenequinhydrone.
authors.affiliation: Laboratoire de thermodynamique et d'électrochimie, Faculté des sciences de Bizerte, 7021 Zarzouna, Bizerte, Tunisia.
authors.forename: Oumayma Ben
authors.initials: OB
authors.lastname: Youchret-Zallez
authors.affiliation: Laboratoire de thermodynamique et d'électrochimie, Faculté des sciences de Bizerte, 7021 Zarzouna, Bizerte, Tunisia.
authors.forename: Salma
authors.initials: S
authors.lastname: Besbes-Hentati
authors.affiliation: UMR 5260, CNRS, Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), Dijon, France.
authors.forename: Marcel
authors.initials: M
authors.lastname: Bouvet
authors.affiliation: Laboratoire de thermodynamique et d'électrochimie, Faculté des sciences de Bizerte, 7021 Zarzouna, Bizerte, Tunisia.
authors.forename: Hechmi
authors.initials: H
authors.lastname: Said
keywords: Calix[4]arenequinhydrone; Charge-transfer complex; Electrochemistry; ITO electrode; UV–Vis spectroscopy