Investigation of electrochemical reduction behaviour of 4-amino-5-hydroxy-3-[(4-nitrophenyl)azo]-6- -(phenylazo)-2,7-naphthalene disulfonic acid disodium salt , (naphthol blue black)

In this study electrochemical behaviour of Disodium 4-amino-5-hydroxy-3-[(4-nitrophenyl)azo]-6-(phenylazo)-2,7-naphthalene disulfonic acid (Naphthol Blue Black Dye) was investigated at mercury working electrode in the range of pH:2.0-12.0 in Britton-Robinson buffer solutions by using SWV, DPP, DCP and CV techniques. The electrode reaction was found to be pH dependent and the increase in pH lead to negative shift of the electrode reaction and also the number of protons and electrons were changed in acidic and basic regions. The azo dye gives a pH-dependent and adsorption complicated electrode reaction and also its found that the electrode reaction has a complex reduction pattern via involving both azo and nitro groups.