A New Electrochemical System Based on a Flow-Field Shaped Solid Electrode and 3D-Printed Thin-Layer Flow Cell: Detection of Pb2+ Ions by Continuous Flow Accumulation Square-Wave Anodic Stripping Voltammetry

Here we investigate the use of 3D printed graphene/PLA electrodes for quantifying trace amounts of Hg, Pb, and Cd. We prepared cylindrical electrodes by sealing a 600 µm diameter graphene/PLA filament in a pipette tip filled with epoxy. We characterized the electrodes using scanning electron microscopy, Raman spectroscopy, and cyclic voltammetry in ferrocene methanol. The physical characterization showed a significant amount of disorder in the carbon structure and the electrochemical characterization showed quasi-reversible behavior without any electrode pretreatment. We then used unmodified graphene/PLA electrode to quantify Hg, and Pb and Cd in 0.01 M HCl and 0.1 M acetate buffer using square wave anodic stripping voltammetry. We were able to quantify Hg with a limit of detection (LOD) of 6.1 nM (1.2 ppb), but Pb and Cd did not present measurable peaks at concentrations below ~400 nM. We improved the LODs for Pb and Cd by depositing Bi microparticles on the graphene/PLA and, after optimization, achieved clear stripping peaks at the 20 nM level for both ions (4.1 and 2.2 ppb for Pb2+ and Cd2+, respectively). The results obtained for all three metals allowed quantification below the EPA action limits in drinking water.

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Trace Analysis of Heavy Metals (Cd, Pb, Hg) Using 3D Printed graphene/PLA Composite Electrodes

10.26434/chemrxiv.10255859.v1 ◽

2019 ◽

Author(s):

John Walters ◽

Shakir Ahmed ◽

Irina Terrero Rodriguez ◽

Glen O'Neil

Keyword(s):

Limit Of Detection ◽

Anodic Stripping Voltammetry ◽

Stripping Voltammetry ◽

Composite Electrodes ◽

Carbon Structure ◽

Anodic Stripping ◽

3D Printed ◽

Pipette Tip ◽

20 Nm ◽

Scanning Electron

Here we investigate the use of 3D printed graphene/PLA electrodes for quantifying trace amounts of Hg, Pb, and Cd. We prepared cylindrical electrodes by sealing a 600 µm diameter graphene/PLA filament in a pipette tip filled with epoxy. We characterized the electrodes using scanning electron microscopy, Raman spectroscopy, and cyclic voltammetry in ferrocene methanol. The physical characterization showed a significant amount of disorder in the carbon structure and the electrochemical characterization showed quasi-reversible behavior without any electrode pretreatment. We then used unmodified graphene/PLA electrode to quantify Hg, and Pb and Cd in 0.01 M HCl and 0.1 M acetate buffer using square wave anodic stripping voltammetry. We were able to quantify Hg with a limit of detection (LOD) of 6.1 nM (1.2 ppb), but Pb and Cd did not present measurable peaks at concentrations below ~400 nM. We improved the LODs for Pb and Cd by depositing Bi microparticles on the graphene/PLA and, after optimization, achieved clear stripping peaks at the 20 nM level for both ions (4.1 and 2.2 ppb for Pb2+ and Cd2+, respectively). The results obtained for all three metals allowed quantification below the EPA action limits in drinking water.

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Determination of copper by anodic stripping voltammetry on a glassy carbon electrode using a continuous flow system

Fresenius Journal of Analytical Chemistry ◽

10.1007/s002160050224 ◽

1997 ◽

Vol 357 (6) ◽

pp. 624-628 ◽

Cited By ~ 7

Author(s):

J. F. van Staden ◽

M. Matoetoe

Keyword(s):

Glassy Carbon Electrode ◽

Glassy Carbon ◽

Continuous Flow ◽

Flow System ◽

Anodic Stripping Voltammetry ◽

Stripping Voltammetry ◽

Carbon Electrode ◽

Anodic Stripping ◽

Determination Of Copper

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Anodic stripping voltammetry using graphite composite solid electrode

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc2009107 ◽

2009 ◽

Vol 74 (11-12) ◽

pp. 1807-1826 ◽

Cited By ~ 1

Author(s):

Tomáš Navrátil ◽

Jiří Barek ◽

Miloslav Kopanica

Keyword(s):

Anodic Stripping Voltammetry ◽

Stripping Voltammetry ◽

Underpotential Deposition ◽

Graphite Powder ◽

Carbon Composite ◽

Graphite Composite ◽

Solid Electrode ◽

Anodic Stripping ◽

Deposition Effect ◽

Composite Solid

A graphite (carbon) composite solid electrode, prepared from graphite powder and epoxy resin, was used as a working electrode for anodic stripping voltammetry. The underpotential deposition effect, which appears at metallic electrodes, was clearly observed on this type of electrode as well. In the case of a simultaneous deposition of two metals on the surface of the composite solid electrode, the anodic dissolution of the metal, which is anodically dissolved at more negative potentials, is substantially influenced by the presence of the other deposited metal. This effect was exploited for the determination of lead in the presence of other metals by differential pulse anodic stripping voltammetry. The article presents possible applicability of such a type of very simple composite electrode to studies of the underpotential deposition effect as well as for analytical purposes.

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