Graphene quantum dots decorated graphene as an enhanced sensing platform for sensitive and selective detection of copper(II)

In this paper, a simple and efficient electrochemical sensing platform was designed based on the hybrid of two carbon nanomaterials for the sensitive and selective detection of trace Cu(II) by using differential pulse anodic stripping voltammetry (DPASV) analysis. The GQDs/graphene/GCE exhibited enhanced electrochemical responses because of a fast electron transfer from graphene and a high affinity to Cu(II) from graphene quantum dots (GQDs). Under the optimal conditions, a good linear response in the range of 0.015-8.775 mu M with correlation coefficient of 0.9995 and a detection limit of 1.34 nM (S/N = 3) were obtained. The developed method was further validated and successfully applied to the detection of Cu(II) in real water samples. The simple preparation and efficient selectivity of the proposed modified electrode show the promising potential for applications in sensing of Cu(II).