A reduced graphene oxide supported Au-Bi bimetallic nanoparticles as an enhanced sensing platform for simultaneous voltammetric determination of Pb (II) and Cd (II)

Abstract

A reduced graphene oxide supported Au-Bi bimetallic nanoparticles (rGO/Au-Bi) have been synthesized and employed as a novel sensing platform for electrochemical determination of Pb2+ and Cd2+ simultaneously. The successful formation of rGO/Au-Bi nanocomposites was investigated by means of transmission electron microscopy and X-ray photoelectron spectroscopy. At the rGO/Au-Bi nanocomposites modified electrode, two well-resolved voltammetric peaks for Pb2+ and Cd2+ were observed in differential pulse anodic stripping voltammetry (DPASV) measurements. Under the optimized conditions (pH 4.5, deposition potential −1.0 V, deposition time 200 s), the DPASV response currents demonstrated good linearity with the concentration of Pb2+ (0.1–500 μg L−1) and Cd2+ (0.1–300 μg L−1). The detection limits was 0.05 μM for Pb2+ and 0.02 μM for Cd2+, respectively. In addition, the proposed electrode exhibited outstanding resistance to potentially interferents, high stability and excellent repeatability. Satisfactory application of proposed electrode was also demonstrated by the determination of Pb2+ and Cd2+ in real river water samples.