Voltammetric and polarographic studies of eriochrome Black T-nickel(II) complex

The electrochemical behaviour of complexes of Eriochrome Black T (EBT) with Ni(II) was studied, It was observed that EBT forms 1:1 and 1:2 complexes w ith Ni(II) in 0.1 M phosphate buffer at pH 6.0 by using Square-wave voltamm etry (SWV), Cyclic voltammetry (CV), Direct Current Polarography (Sampled D CP) and Controlled Potential Coulometry (CPC). It was found that the reduct ion processes of Ni(II)-EBT complexes are irreversible. The stability const ants of the Ni(II)-EBT complexes were evaluated with the DeFord-Hume proced ure at different ligand concentrations using SWV. The logarithm Values of s tability constants of 1:1 and 1:2 Ni(II)-EBT complexes are 8.17 and 11.17, respectively.