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• In this paper, we report the corrosion inhibition of amino acid imidazole ionic liquids ([CyVIm][AA]ILs) on mild steel in neutral media, which has not been studied before. • In addition, the corrosion inhibition performance of [CyVIm][AA]ILs in neutral media was evaluated comprehensively by a combination of experiments and simulations as well as an in-depth investigation of the corrosion inhibition mechanism. The corrosion inhibition properties of three amino acid imidazole ionic liquids ([CyVIm][AA]) as corrosion inhibitors for mild steel in a 3.5 wt% NaCl corrosion medium were evaluated by electrochemical measurements. The polarization experiments show that [CyVIm][AA] influences anode reaction processes, demonstrating that [CyVIm][AA] is an anodic inhibitor type corrosion inhibitor. [CyVIm]Try outperforms [CyVIm]His and [CyVIm]Pro in terms of corrosion inhibition. The results of surface analysis and quantum chemical calculations show that [CyVIm]Try can form a protective film on the surface of mild steel and inhibit surface corrosion. Furthermore, by applying molecular dynamics simulations, after investigating the corrosion inhibitor adsorption trends on the Fe (1 1 0) surface, the interaction order between the molecular framework of the Fe corrosion inhibitor and the Fe (1 1 0) surface for entanglement was determined. According to the radial distribution function, the corrosion inhibitor adsorption mode on the metal surface is composite adsorption with chemisorption as the major mode and physical adsorption as the secondary mode. [ABSTRACT FROM AUTHOR]

• Porphyrins with different number of electroactive substituents. • Effect of porphyrin structure on the film formation and film properties. • Mechanism and kinetic of oxygen electroreduction on the films. • Difference in films morphology, activity and, probable, in catalytic site density. The paper analyzes how the structure of porphyrin affects its electrochemical characteristics, film formation process and physicochemical properties of the obtained materials. A comparison of the redox processes of 21H,23H-5,15-bis-(4-aminophenyl)-10,20-di-phenyl porphyrin (Porph I) and 21H,23H-5,10,15-tris-(4-aminophenyl)-20-phenyl porphyrin (Porph II) shows that Porph I is more stable in oxidation and less stable in reduction processes than Porph II. The presence of electrochemically active amino groups in the composition of the porphyrin molecules allows the superoxide-assisted electrochemical deposition method to be applied to successfully form poly-Porph I and poly-Porph II films from dimethyl sulfoxide solutions. Spectral methods confirm that the obtained materials preserve their porphyrin structure. The structure of the initial monomer molecules is demonstrated to affect the film formation and surface morphology of the prepared materials. Oxygen electroreduction in an alkaline medium is shown to have smaller kinetic limitations on poly-Porph II films than that on poly-Porph I ones. [ABSTRACT FROM AUTHOR]

This review overviews and revalues the role that the electrochemical techniques and the continuously evolving electrode designs play in the tremendous progress experienced by electrochemical biosensing. These aspects are scarcely covered in the recent literature on electrochemical biosensors and are discussed in this article through selected representative examples together with other approaches involving the use of signal amplification strategies, electrocatalytic materials, ratiometric designs or antifouling chemistries. Regarding electrodes, the continuous advances made in screen-printed, micro-, paper-based and flexible and wearable materials are critically overviewed. Concerning electrochemical techniques, the use of selected widely known techniques (electrochemical impedance spectroscopy, stripping voltammetry, and potentiometry) to successfully address different applications in response to current biosensing challenges is highlighted through their smart coupling with new experimental designs, bioreceptors and materials. [ABSTRACT FROM AUTHOR]

• Effects of thermodynamic and kinetic dispersion in surface confined voltammetry. • Distinguishing dispersed from non-dispersed cases by looking at voltammetry data. • Thermodynamic dispersion is usually resolvable for all experiments. • Kinetic dispersion is only resolvable for certain systems under defined conditions. Dispersion, or the distribution of kinetic and thermodynamic parameter values describing a redox reaction, has long been acknowledged as a complicating factor in the analysis of both solution and surface-confined voltammetry experiments. In this tutorial paper, we show how varying levels of dispersion can affect the appearance of the experimental current, mainly illustrating the concept with reference to surface-confined reversible one electron transfer. We focus on three voltammetric techniques, ramped Fourier Transform AC Voltammetry, Purely Sinusoidal Voltammetry and Direct Current Voltammetry, showing the effect the dispersion parameters have on the appearance of the resulting current. We have also implemented an interactive web-based simulation package for comparison of the effects of the various parameters, available here. As modelling dispersion significantly increases the computational burden of simulating voltammetry experiments, making well-informed choices about when to include this effect is essential. To facilitate this, we discuss the intuition for when to include dispersion when fitting experimental voltammetry data, again with reference to the three techniques described above. [ABSTRACT FROM AUTHOR]