3D‐printed Metal Electrodes for Heavy Metals Detection by Anodic Stripping Voltammetry

Abstract

Heavy metals, being one of the most toxic and hazardous pollutants in natural water, are of great public health concern. Much effort is still being devoted to the optimization of the electroanalytical methods and devices, particularly for the development of novel electrode materials in order to enhance selectivity and sensitivity for the analysis of heavy metals. The ability of 3D‐printing to fabricate objects with unique structures and functions enables infinite possibilities for the creation of custom‐made electrochemical devices. Here, stainless steel 3D‐printed electrodes (3D‐steel) have been tested for individual and simultaneous square wave anodic stripping analysis of Pb and Cd in aqueous solution. Electrodeposition methods have also been employed to modify the steel electrode surface by coating with a thin gold film (3D−Au) or a bismuth film (3D−Bi) to enhance the analytical performance. All 3D‐printed electrodes (3D‐steel, 3D−Au and 3D−Bi) have been tested against a conventionally employed glassy carbon electrode (GC) for comparison. The surface modified electrodes (3D−Au and 3D−Bi) outperformed the GC electrode demonstrating higher sensitivity over the studied concentration ranges of 50–300 and 50–500 ppb for Pb and Cd, respectively. Owing to the bismuth property of binary alloys formation with heavy metals, 3D−Bi electrode displayed well‐defined, reproducible signals with relatively low detection limits of 3.53 and 9.35 ppb for Pb and Cd, respectively. The voltammetric behaviour of 3D−Bi electrode in simultaneous detection of Pb and Cd, as well as in individual detection of Pb in tap water was also monitored. Overall, 3D‐printed electrodes exhibited promising qualities for further investigation on a more customizable electrode design.

Accounts in 3D‐Printed Electrochemical Sensors: Towards Monitoring of Environmental Pollutants

“…A helical-shaped 3D-printed stainless steel electrode has been printed by SLM technique and tested for simultaneous determination of Pb 2 + and Cd 2 + in aqueous samples via square wave anodic stripping analysis. [42] The analytical method is based on pre-concentrating the analyte on the electrode surface followed by the stripping voltammetric scan which allows enhanced signals, while the combination with square wave voltammetry produces a fast and sensitive scan. Since the as-printed working electrode demonstrated poor electroanalytical performances for heavy metals determination when compared with a reference standard electrode like glassy carbon, the as-printed electrode was functionalized by depositing either Au or Bi through electro-plating procedures.…”

Trace Analysis of Heavy Metals (Cd, Pb, Hg) Using Native and Modified 3D Printed Graphene/Poly(Lactic Acid) Composite Electrodes

“…SLS has been used primarily by Pumera's group to produce stainless steel electrodes [27]. The SLS electrodes have been used for fabricating sensors for DNA [28,29], heavy metals [30], various toxins [31], as well as for energy related applications [27,32,33]. FDM is used to produce conducting thermoplastics such as nylon, acrylonitrile butadiene styrene (ABS), and poly (lactic acid) (PLA), which are made conductive by adding carbon to the polymer matrix [34][35][36].…”

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

“…SLS has been used by Pumera's group to produce stainless steel electrodes. [27] The SLS electrodes have been used for fabricating sensors for DNA, [28,29] heavy metals, [30] various toxins, [31] as well as for energy related applications. [27,32,33] FDM is used to produce conducting thermoplastics such as nylon, acrylonitrile butadiene styrene (ABS), and poly(lactic acid) (PLA), which are made conductive by adding carbon to the polymer matrix.…”