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.