Cyclic Voltammetric Investigation of Eu3+ on a MWCNTs/SDS-Modified Glassy Carbon (GC) Electrode

Electrochemical reduction behavior of Eu3+ on a multi-walled carbon nanotubes (MWCNTs)/sodium lauryl sulfate (SDS) (MWCNTs/SDS)-modified glassy carbon (GC) electrode was investigated by cyclic voltammetry (CV). Results indicated that the electrochemical reduction process of Eu3+ at the MWCNTs/SDS-modified GC electrode is a quasi-reversible and diffusion-controlled process. The value of standard rate constant (k(s)) at the MWCNTs/SDS-modified GC electrode was estimated to 1.96 x 10(-2) cm s(-1). CV studies showed that the electrochemical response of Eu3+ was directly related to the ratio of MWCNTs to SDS, and the tube diameter of MWCNTs had a slight influence on the electrochemical behavior of Eu3+, whereas the tube length. of MWCNTs had a strong influence. CVs results also proved that s-MWCNTs (with shorter tube length)-modified GC electrode showed better response to the electrochemical reaction of Eu3+.