Electrochemical Behaviour and Electronic Absorption of the Metal β- Diketonates Complexes

Abstract

The electrochemical properties of -diketonate complexes, such as [Co(tta)2(H2O)2], [Ni(tta)2(H2O)2], [Cu(tta)2] and [Zn(tta)2(H2O)2] (tta = deprotonated of 1-thenoyl-4,4,4-trifluoroacetone) have been studied using cyclic voltammetry (CV). Their redox behaviors including oxidation and/ or reduction process for both central atom and tta ligand have been discussed. The cyclic voltammogrammes display one irreversible oxidation peak in a positive potential region, where it appears in the area between + 1.30 and + 1.95 V based on the type of complex. In addition, two reduction peaks are appeared in the negative region potentials, at the region between – 1.06 to – 2.16 V. The irreversible oxidation potential peak of thienyl ring has shifted to the lower positive potential, while the reversibly redox potential peak of the fluorinated--diketone moiety shifts to the higher negative potential compared with non-coordinated H-tta ligand. The spectral properties, energy levels, and energy gap for the respective complexes have been verified with UV-Vis spectrophotometer.