Graphene oxide amplified electrochemiluminescence of graphitic carbon nitride and its application in ultrasensitive sensing for Cu2+

Here for the first time, we present a novel electrochemiluminescence (ECL) sensor based on graphitic carbon nitride/graphene oxide (g-C3N4/GO) hybrid for the ultrasensitive detection of Cu2+, which is a common pollutant in environmental system. The g-C3N4/GO shows stable ECL signal in the presence of the self-produced coreactant from oxygen reduction, and the ECL signal could be effectively quenched by Cu2+, the possible ECL detection mechanism has been proposed in detail. GO can not only significantly enhance the cathodic ECL signal of g-C3N4 (similar to 3.8 times), but also serve as immobilization platform for g-C3N4. After optimization of experimental conditions, the proposed protocol can offer an ultrasensitive, highly selective and recyclable method for the detection of Cu2+ with a low detection limit of 1.0 x 10(-11) M and a wide linear range from 1.0 x 10(-11) to 1.0 x 10(-7) M. Moreover, the practicability of the ECL sensor in real wastewater samples is also tested, showing that the proposed ECL sensor could be a promising alternative method for the emergency and routine monitoring of Cu2+ in real sample. (C) 2015 Elsevier B.V. All rights reserved.