Determination of Hg(II) with square-wave anodic stripping voltammetry method on AuNPS/ErGO-GCE electrode

Abstract

In this study, Hg(II) was determined on a modified AuNPs/ErGO-GCE electrode with the square-wave anodic stripping voltammetry (SqW-ASV) method. The morphology of the material modifying the electrode was characterized with EDX-mapping and HR-TEM. Additionally, several parameters of the SqW-ASV method, including pulse amplitude (ΔE), square wave frequency (f), potential change step (r), deposition potential (E_dep.), and deposition time (t_dep.), were investigated. Under optimized conditions: acetate buffer (ABS), pH = 5 and KCl 0.1 M, r from –0.2 to +0.8 V, E_dep: –0.9 V, t_dep: 240 s, DE: 30 mV and f: 30 Hz, the linear range of Hg(II) concentration was from 5.0 to 49,5 ppb, and the detection limit of Hg(II) was 1.89 ppb.