Cathodic electrochemiluminescence of luminol using polyaniline/ordered mesoporous carbon (CMK-3) hybrid modified electrode for signal amplification

A highly porous three-dimensional sensing interface was achieved on glassy carbon (GCE) by employing ordered mesoporous carbon (OMC) and polyaniline (PANI). Compared with the cathodic electrochemiluminescence (ECL) of luminol at bare glassy carbon electrode, a stable and intense cathodic ECL emission of luminol over -0.5 V which related to the reduction of dissolved oxygen in solution was triggered at OMC and PANI constructed ECL sensing platform. The influence factors affecting the electrode configuration such as the concentration of OMC, the dripping amount of OMC, the polymerization cycles of PANI and the pH value of buffer solution on cathodic ECL intensity of luminol were investigated in detail. The PANI/CMK composite modified electrode exhibited an effective ECL platform for cathodic ECL of luminol due to its attractive features, such as excellent electrical conductivity, extremely well-ordered pore structure and high specific pore volume. The possible ECL mechanism was discussed according to the presented experimental results. (C) 2012 Published by Elsevier Ltd.