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Implicit anodic and cathodic current components associated with the real net current at a given potential of a simple quasireversible electrode reaction can be accurately estimated using basic mathematical modeling within the framework of Butler-Volmer electrode kinetics. This methodology requires only prior knowledge of the formal potential of the dissolved redox couple, offering direct insight into the electrode kinetics. The proposed approach facilitates a unique transformation of a conventional cyclic voltammogram, allowing the replacement of the common, net current with authentic anodic and cathodic current components. This simple methodology introduces a novel perspective in analyzing voltammetric data, particularly enabling the kinetic characterization of fast, seemingly electrochemically reversible electrode processes on macroscopic electrodes at slow scan rates. Theoretical predictions are experimentally demonstrated using the electrode reaction for the reduction of the hexaammineruthenium(III) complex, serving as an example of one of the fastest electrode processes involving a dissolved redox species. [ABSTRACT FROM AUTHOR]

Neonicotinoids, as the fastest-growing class of insecticides, currently account for over 25% of the global pesticide market. Their effectiveness in controlling a wide range of pests that pose a threat to croplands, home yards/gardens, and golf course greens cannot be denied. However, the extensive use of neonicotinoids has resulted in significant declines in nontarget organisms such as pollinators, insects, and birds. Furthermore, the potential chronic, sublethal effects of these compounds on human health remain largely unknown. To address these pressing issues, it is crucial to explore and understand the capabilities of electrochemical sensors in detecting neonicotinoid residues. Surprisingly, despite the increasing importance of this topic, no comprehensive review article currently exists in the literature. Therefore, our proposed review aims to bridge this gap by providing a thorough analysis of the use of electrochemical methods for neonicotinoid determination. In this review article, we will delve into various aspects of electrochemical analysis, including the influence of electrode materials, employed techniques, and the different types of electrode mechanisms utilized. By synthesizing and analysing the existing research in this field, our review will offer valuable insights and guidance to researchers, scientists, and policymakers alike. [ABSTRACT FROM AUTHOR]

Energy crisis of the current society have attract the research attention for alternative energy sources. Methanol oxidation is source of energy but need efficient electrocatalyst like Pt. However, their practical ability is hinder due to cost and poisoning effect. In this regard, efficient catalyst is required for methanol oxidation. Herein, high temperature, pressure, and diethylenetryamine (DETA) as reaction medium/structure directing agent during solvothermal method are used for nanobelt Cu3Se2/Cu1.8Se (mostly hexagonal appearance) formation. The electrocatalyst shows optimized methanol electrooxidation reaction (MOR) response in 1 M KOH and 0.5 M methanol at scan rate of 50 mV/s and delivers a current density 7.12 mA/mg at potential of 0.65 V (vs Ag/AgCl). The catalyst exhibits high electrochemical active surface area (ECSA) (0.088 mF/cm2) and low Rct with good stability for 3600 s which favor its high MOR performance. This high response is due to its 2D hexagonal nanobelt morphology, which provides large surface area for reaction. The space among nanobelt reduce diffusion kinetics and rough/irregular edge increase reaction site to overall improve the methanol oxidation reaction. [ABSTRACT FROM AUTHOR]

Single-step solvothermal method is used to prepare Cu/CuSe as an electrocatalyst for methanol electro-oxidation reaction (MOR). 1,3-butan-diol is selected as a reaction medium, whose viscosity and complex formation with Cu(II) ions dictate the catalyst morphology. The catalyst has a macroporous structure, which is composed of nanoballs with a high purity, crystallinity, and uniform morphology. The electrocatalyst is excellent for MOR, as it delivers current density of 37.28 mA/mg at potential of 0.6 V (vs Ag/AgCl) in the electrolyte of 1 M KOH and 0.75 M methanol at a 50 mV/s scan rate under conditions of cyclic voltammetry. The catalyst also shows good stability for 3600 s with negligible charge transfer resistance and high electrochemical active surface area (ECSA) value of 0.100 mF/cm2. [ABSTRACT FROM AUTHOR]

Reaction medium (1,3-butane-diol) plays a vital role for the final morphology of W-Mo15Se19 electrocatalyst during synthetic strategy based on single-step solvothermal method. Smoothness of the electrocatalyst may govern its electrochemical application. High ECSA (0.055 mF/cm2), low Rct, low Tafel slope (99.0 mV/dec), and excellent long-term stability for 3600 s may attribute to its large surface area due to negligible agglomeration. W-Mo15Se19 delivers a current density of 1.65 mA/mg at an overpotential of 0.65 V (Ag/AgCl) in 0.75 M methanol and 1 M KOH, at a scan rate of 50 mV/s. [ABSTRACT FROM AUTHOR]

The increasing use of pesticides is a major health issue. There is therefore a need for improved analytical methods and more knowledge on the interaction of pesticides with living organisms. Here, we developed the analysis of profluralin in water and soils by cyclic voltammetry, square-wave voltammetry and square-wave adsorptive stripping voltammetry. We also studied the interaction between profluralin and double-stranded DNA. Results of cyclic voltammetric studies indicate that the reduction processes have an irreversible and adsorption-like character, as a possible consequence of the reduction of nitro groups of profluralin. Quantification was found linear from 60 to 800 nmol L−1 with a detection limit of 17 nmol L−1 using square-wave adsorptive stripping voltammetry. Results of interactions with double-stranded DNA from salmon sperm revealed that profluralin forms a complex with DNA by electrostatic binding. Values of Gibbs free energy confirmed that formation of profluralin–DNA complex is spontaneous and favourable. [ABSTRACT FROM AUTHOR]

The use of square wave voltammetry (SWV) and square wave adsorptive stripping voltammetry (SWAdSV) in conjunction with a cyclic renewable silver amalgam film electrode for the determination of flumetralin is presented. Poor separation of two overlapped reduction peaks is significantly improved when hexadecyltrimethylammonium bromide is used as a component of the supporting electrolyte solution (together with BR buffer pH 9.5). The SW technique parameters were investigated and found optimal as follows: frequency 50 Hz, amplitude 40 mV, and step potential 5 mV. Accumulation time and potential were studied to select the optimal conditions in adsorptive voltammetry. The analytical curve was linear for the flumetralin concentration range from 1.0 × 10 to 1.0 × 10 mol dm and from 5.0 × 10 to 1.0 × 10 mol dm for SWV and SWAdSV, respectively. Detection limit of 6.5 × 10 mol dm was calculated for accumulation time 60 s at −0.2 V. The repeatability of the method was determined at a flumetralin concentration level equal to 5.0 × 10 mol dm and expressed as %RSD = 5.0% ( n = 6). The proposed method was applied and validated successfully by studying the recovery of herbicide content in spiked environmental samples. Graphical abstract: [ABSTRACT FROM AUTHOR]

We examined the electroreduction of Bi (III) ions in chlorate (VII) solutions under varied protonation conditions of the depolariser using voltammetric and impedance methods. The results of the kinetic parameter correlation lead to the statement that the changes in the amount of chloric (VII) acid against the amount of its sodium salt in the supporting electrolytes of the low water activity have a significant influence on the rate of Bi (III) ion electroreduction. The increase of the concentration of chloric acid sodium salt, as well as the chloric (VII) acid alone within the particular concentration of the supporting electrolyte, inhibits the process of Bi (III) ion electroreduction. It should be associated with the reorganisation of the structure of the double layer connected with the slow dehydration inhibited by ClO ions. The standard rate constants k values with the increase of the chlorate (VII) concentrations for all the solutions examined of chlorates (VII) confirms the catalytic influence of the decrease of water activity on the process of Bi (III) ion electroreduction. The multistage process is confirmed by the non-rectilinear 1n k = f( E) dependences. [ABSTRACT FROM AUTHOR]

The pesticide diazinon was determined in its insecticidal formulations by square wave adsorptive stripping voltammetry. The method of its determination is based on the irreversible reduction reaction at the hanging mercury drop electrode. The optimal signal was detected at −1.05 V vs. Ag/AgCl in Britton-Robinson buffer at pH 4.4. Various parameters such as pH, buffer concentration, frequency, amplitude, step potential, accumulation time, and potential were investigated to enhance the sensitivity of the determination. The highest response was recorded at an accumulation potential −0.4 V, accumulation time 60 s, amplitude 75 mV, frequency 100 Hz, and step potential 5 mV. The pesticide electrochemical behavior was considered under experimental conditions. The electroanalytical procedure enabled diazinon determination in the concentration range 4.0 × 10-3.9 × 10 mol L in supporting electrolyte. The detection and quantification limit were found to be 1.1 × 10 and 3.7 × 10 mol L, respectively. The method was applied successfully in the determination of the active ingredients in the insecticidal formulations Diazinon 10GR and Beaphar 275. [ABSTRACT FROM AUTHOR]

Clothianidin, a new generation of pesticide, was determined in spiked tap water, apple juice, and soil by square-wave adsorptive stripping voltammetry. The method of determination is based on the hydrogen evolution reaction catalyzed by clothianidin at the hanging mercury drop electrode. The optimal signal was detected at −1.4 V versus Ag/AgCl in citrate buffer at pH 2.2. Various parameters such as pH, buffer concentration, frequency, amplitude, step potential, accumulation time, and potential were investigated to enhance the sensitivity of the determination. The optimal results were recorded at an accumulation potential of −0.35 V, accumulation time of 7 s, amplitude of 100 mV, frequency of 200 Hz, and step potential of 7 mV. The mechanism of catalytic hydrogen evolution was considered under experimental and theoretical conditions. This electroanalytical procedure enabled to determine clothianidin in the concentration range 9 × 10-4 × 10 mol L in supporting electrolyte and tap water, 1 × 10-4 × 10 mol L in diluted apple juice, and 2 × 10-1 × 10 mol L in soil. The detection and quantification limits in supporting electrolyte and diluted apple juice were found to be 2.6 × 10, 8.6 × 10 and 3 × 10, and 1 × 10 mol L, respectively. A standard addition method was successfully used to determine clothianidin in spiked tap water, spiked apple juice, and spiked soil. [ABSTRACT FROM AUTHOR]