Electrogenerated chemiluminescence of luminol at a carbon nanotube-perfluorosulfonate polymer (Nafion) modified gold electrode

A multi-wall carbon nanotube/Nafion modified gold electrode (CNT/Nafion/GE) was fabricated by casting the composite film on the electrode surface. Electrogenerated chemiluminescence (ECL) of luminol at the modified gold electrode was studied under conventional cyclic voltammetry in alkaline Na2CO3-NaHCO3 buffer solution. Three ECL peaks were obtained. The most strong ECL peak (ECL-1) was enhanced about 20-fold at the CNT/Nafion modified gold electrode compared with that at the bare gold electrode. The emitter of all the ECL peaks was indentified as 3-aminophthalate. The intensities of ECL peaks were found to depend on the ratio of CNT/Nafion, the electrolytes, the pH, and the presence of O2 and N2. The mechanisms of all ECL peaks have been proposed. The results indicate that carbon nanotubes have a significantly catalytic effect on luminol ECL, which might further expand the analytical application of nanomaterial-modified electrode in the field of electrogenerated chemiluminescence.