Catalytic Adsorptive Stripping Voltammetric Determination of Germanium Employing the Oxidizing Properties of V(IV)-HEDTA Complex and Bismuth-Modified Carbon-Based Electrodes

Abstract

An efficient procedure that may be used to determine germanium traces and combines the advantages of catalytic adsorptive stripping voltammetry (CAdSV) with the convenience of screen-printed electrodes was developed. To induce the CAdSV response of the germanium(IV)-catechol complex, the vanadium(IV)-HEDTA compound was employed in combination with various bismuth-modified homogeneous (glassy carbon, gold coated with a bismuth layer via physical vapor deposition) and heterogeneous (screen-printed carbon, mesoporous carbon, graphene and reduced graphene oxide, polymer-encapsuled carbon fiber) electrodes. This solution had never before been implemented for this purpose. To achieve the most favorable performance of the working electrode, the parameters of bismuth deposition were optimized using a central composite design methodology. SEM imaging and contact angle measurements confirmed the long-term stability and high chemical resistance of the electrodes against the oxidizing action of V(IV)-HEDTA. Under optimized conditions, the method made it possible to detect nanomolar concentrations of germanium with favorable detection limits, high sensitivity, and a wide linear range of 5–90 nM of Ge(IV).

Simple Voltammetric Determination of Iron in Ethanol and Biodiesel Using a Bismuth Film Coated Glassy Carbon Electrode

“…The use of SWAdSV and bismuth film electrode for the determination of iron in biofuels is an alternative method that enables the detection of low concentrations in complex samples as biofuels. The work of Wang et al (2022) and Kr olicka, Zarbebski and Bobrowski (2021) reinforce the versatility of the bismuth film as electrochemical sensors widely used for the determination of metals other than iron.…”

Preparation, Characterization, and Activation of Natural Glassy Carbon Paste Electrodes as New Sensors for Determining the Total Antioxidant Capacity of Plant Extracts

“…Another parameter that was used for the characterization of GCn is the contact angle. The contact angle for GCn is slightly higher than that measured for both laboratory synthesized GCs and glassy carbon used for the construction of commercial glassy carbon electrodes, GCE [30], but the obtained value of to 86 ± 1° is close to the 80°, a value typical for glassy carbon (Figure 1b) [28]. Another parameter that was used for the characterization of GC n is the contact angle.…”

Bridging Virtual and Reality: Testing Design of Experiment Procedures with Simulated and Experimental Data

“…A prominent maximum is observed for a solution containing 16.7 mM bismuth, with a plating potential of −1.156V, and electrolysis performed to exchange a charge of 42.8 mC. In previous studies [4], the peak of the CCD surface was outside the experimental domain. The optimal plating parameters included a plating potential of −0.9 V and other variables at their maximum investigated values (40 mM Bi(III) ion concentration, 50 mC).…”

“…Electrochemical studies aimed at the determination of germanium [4] and the determination of the antioxidant capacity of plant infusions were performed on an Autolab 204 analyser (Metrohm Autolab, Switzerland). Commercial glassy carbon disc electrodes (3 mm in diameter, Mineral, Poland) were used as working electrodes.…”

“…After the studies using virtual data, the CCD was used to optimise the experimental parameters in real-life voltammetric measurements. The determination of germanium through catalytic adsorptive stripping voltammetry with a bismuth film electrode has previously been described [4]. Figure 3 shows the response surface profiles for the germanium peak current as a function of charge and plating potential (Figure 3a), as well as the correlation plot of predicted versus observed values (Figure 3b).…”