Few-layer binder free graphene modified mercury film electrode for trace metal analysis by square wave anodic stripping voltammetry

Abstract

A binding agent free graphene modified glassy carbon electrode in combination with an in situ plated mercury film electrode (Gr-GC-HgFE) was used as a highly sensitive electrochemical platform for the determination of Zn2+, Cd2+ and Pb2+ in 0.1 M acetate buffer (pH 4.6) by square-wave anodic stripping voltammetry (SWASV). Instrumental parameters such as deposition potential, deposition time and electrode rotation speed were optimized. The Gr-GC-HgFE sensing platform exhibited improved sensitivity for metal ion detection, in addition to well defined, reproducible and sharp stripping signals. Two linear calibration curves ranging from 0 –10 μg L−1 and 0 – 60 μg L−1 were identified yielding detection limits of 0.08 μg L−1, 0.05 μg L−1 and 0.14 μg L−1 for Zn2+, Cd2+ and Pb2+, respectively, for simultaneous analysis and 0.04 μg L−1, 0.11 μg L−1 and 0.14 μg L−1 for Zn2+, Cd2+ and Pb2+, respectively, for individual analysis when using a deposition time of 120 s. For practical applications recovery studies using tap water samples spiked with target metal ions gave recoveries within 10% of the spiked amount. Much better recoveries were obtained for the individual analysis in comparison with simultaneous analysis.

Description

Keywords

Graphene, Modified mercury film, Square wave anodic stripping voltammetry, Heavy metals

Citation

Zbeda, S. et al. (2013). Few-layer binder free graphene modified mercury film electrode for trace metal analysis by square wave anodic stripping voltammetry. International Journal of Electrochemical Science, 8: 11125-11141