Enhanced voltammetric determination of metal ions by using a bismuthene-modified screen-printed electrode

Abstract

• Bismuthene modified screen-printed carbon electrode (2D bi exf -SPCE) is proposed for the determination of Pb(II) and Cd(II) metal ions by DPASV. • Exfoliated layered bismuth (2D Bi exf ) was easily attached on SPCE by drop-casting. • Improved sensitivities and LODs are achieved when using 2D bi exf -SPCE instead of Bare-SPCE, BiNP-SPCE and bi sp SPE. • Reliable and very high reproducibility in the analysis of a certified estuarine water reference material. A new bismuthene carbon-based screen-printed electrode (2D Bi exf –SPCE) was easily prepared, taking advantage of the strongest features of exfoliated layered bismuth (bismuthene) for metal ions detection by differential pulse anodic stripping voltammetry (DPASV). An exfoliated bismuth suspension was drop-casted on the working electrode surface of a screen-printed carbon electrode (SPCE), giving rise to the 2D Bi exf –SPCE. It was microscopically and analytically examined and compared not only with bare SPCE but also with other bismuth-based screen-printed sensors that report good analytical performance, i.e., bismuth nanoparticle-modified SPCE (BiNP-SPCE) and sputtered bismuth SPE (Bi sp SPE). Under improved conditions and for a 120 s preconcentration time, the sensor exhibits good correlation between peak area and metal concentration in the range 0.2–25.0 μg L −1 for both Pb(II) and Cd(II) with LODs (3 times the standard deviation of the intercept over the slope of the linear calibration curve) of 0.06 and 0.07 μg L −1 for Pb(II) and Cd(II), respectively. 2D Bi exf –SPCE has been successfully applied to a certified estuarine water reference material with excellent trueness and remarkable reproducibility.