The Application of 2,6-Dichlorophenolindophenol-Functionalized Carbon nanotubes for Electrocatalytic Determination of Sulfide Ions

A chemically modified glassy carbon electrode was developed using multi-walled carbon nanotubes covalently immobilized with 2,6-dichlorophenolindophenol. The immobilization of 2,6-dichlorophenolindophenol with multi-walled carbon nanotubes was characterized by UV–visible absorption spectroscopy and Fourier transform infrared spectroscopy, and was determined using cyclic voltammetry. The cyclic voltammetric response of 2,6- dichlorophenolindophenol grafted onto multi-walled carbon nanotubes indicated that it promoted the electrocatalytic, sensitive and stable determination of sulfide ions. Meanwhile, the dependence of response currents on the concentration of sulfide was also examined and was linear in the range of 1.8 μM – 2.5 mM. The detection limit of sulfide was 1.1 μM, and RSD for 10 and 1000 μM sulfide was 1.8 and 1.3 %, respectively. Many interfering species had little or no effect on the determination of sulfide. This procedure was applied for determination of sulfide in water samples.