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The damage to a metal is significantly enhanced when simultaneously exposed to a corrosive solution and a cyclic mechanical stress. However, decoupling the contributions from each damage mechanisms is difficult. Localised electrochemical techniques, in particular scanning electrochemical microscopy (SECM), scanning electrochemical cell microscopy (SECCM), scanning kelvin probe force microscopy (SKPFM), and scanning vibrating electrode technique (SVET), can be advantageous when determining corrosion fatigue damage mechanisms and local phenomena, such as the transition between a corrosion pit and a fatigue crack. The recent corrosion fatigue literature is reviewed to highlight the usefulness of each localised electrochemical technique and how they can contribute to advancing the corrosion fatigue field. [Display omitted] [ABSTRACT FROM AUTHOR]

The work presented here describes the development and characterization of platinum-mercury hemispherical nanoelectrodes for the spatially resolved quantitative detection of manganese cations. The electrochemical probes were made by electrodeposition of metallic mercury from a mercuric ion solution onto Pt/quartz laser-pulled concentric disk nanoelectrodes (with disk radii ranging from 3 to 500 nm). The nanoelectrodes were characterized by steady-state voltammetry, scanning electrochemical microscopy, environmental scanning electron microscopy, energy-dispersive X-ray spectroscopy and calibrated with respect to the concentration of Mn 2+ ions using anodic stripping voltammetry. The fully characterized probes were employed for the quantitative detection of Mn 2+ . The technique has been used to evaluate the impact of a novel approach for mitigating the undesirable consequences of manganese dissolution in Li-ion batteries. [ABSTRACT FROM AUTHOR]

The corrosion of an AM50 Mg alloy was studied in ethylene glycol using electrochemical and electron microscopy techniques. Switching from H 2 O to ethylene glycol, it was shown that the corrosion of the AM50 alloy was significantly suppressed thereby slowing H 2 evolution. The corrosion of the AM50 alloy was mapped using scanning electrochemical microscopy in the feedback mode. Ferrocenemethanol can be used to expose the reactive anodic areas on the Mg alloy. These studies confirmed that studies in ethylene glycol can be used to elucidate reaction features obscured by rapid corrosion in H 2 O without significantly altering the mechanism and damage morphology. [ABSTRACT FROM AUTHOR]

Quantitative in-situ and localized analytical methods that can monitor Mg 2+ release are central to probe the impact of the microstructure on magnesium alloy corrosion. As such, a potentiometric micro-Mg 2+ ion-selective membrane electrode is fabricated, calibrated, characterized and used to selectively monitor the Mg 2+ release from different cast Mg AM50 alloys during corrosion. We demonstrate that the local Mg 2+ release is tied to the alloy microstructure and its aluminum distribution, indicating a possibility of optimization of the base material corrosion properties. [ABSTRACT FROM AUTHOR]

Maintaining a well-defined tip-to-substrate separation is a critical area of development in scanning electrochemical microscopy (SECM). One technique that provides topographic data independently to the electrochemical measurement is shear force (SF) SECM. SF measurements are highly sensitive to factors including the tip-to-substrate separation, experimental solution, and probe geometry. We present a procedure for the fabrication of highly reproducible electrochemical probes with an active electrode disc with radii between 3nm to 190nm. A systematic study of the SF characteristics of these nano electrodes provides details on how to achieve the highest sensitivity and stability of SF signals, and maximize the number of SF sensitive frequencies. A new methodology to identify SF sensitive frequencies without needing to immerse the probes in solution or approach the surface is presented. Furthermore, we demonstrate that the greatest source of error in achieving reproducible SF behavior lies in the positioning of the piezo electric components and the piezo-nano electrode interface. [ABSTRACT FROM AUTHOR]

Highlights: [•] Detection of local flux of H2 for the analysis of the corrosion behavior of microstructural features. [•] SECM maps and approach curves measurement showed time-dependent change of the corrosion process. [•] Numerical simulations revealed a continual change in the size of active site and the local flux of H2 formation. [ABSTRACT FROM AUTHOR]

Abstract: Scanning electrochemical microscopy (SECM) is increasingly applied to study and image live cells. To reduce the overall analysis time during live cell SECM measurements and maintain cell viability, the microelectrode scan rate can be increased. The use of increasing microelectrode scan rates is challenging because our understanding of the downstream convection effects is tied to the ill-defined topography of the imaged live cells. The present study investigates the effect of forced convection on the microelectrode current during SECM imaging of live cells, model non-planar substrates and planar surfaces. Experimentally, we demonstrate that during constant height imaging, the normalized peak current observed during line scans on all three substrates scales linearly with the microelectrode velocity. This quasi-linear relationship is corroborated by finite element simulations of non-planar substrates, which further reveal that the slope is closely related to the electrochemical activity of the substrate. [Copyright &y& Elsevier]

CO 2 reduction offers an attractive alternative green synthetic route for ethylene, especially where CO 2 could be sourced from industrial exhausts and in combination with green power sources. However, practical applications are currently limited due to the unfortunately low selectivity of cathode materials towards ethylene. This work uses polymers with intrinsic microporosity (PIMs) to improve the performance of copper gas diffusion electrodes for CO 2 reduction to ethylene. We report an improved selectivity and activity towards ethylene with the addition of a thin PIMs layer, which is seen as improved Faradaic efficiency, increased stability and a shift in the reduction to lower overpotential. This improvement is highly dependent on the thickness of the added polymer layer, with too thick a layer having a detrimental impact on the hydrophobicity of the gas diffusion layer. With a compromise in loading, PIMs can be used to enhance the activity and selectivity of catalysts for targeted CO 2 reduction to ethylene. Image 10694 • Gas diffusion electrodes allow CO 2 reduction to ethylene, but selectivity is low. • Polymers with intrinsic microporosity can increase ethylene production. • Using too much polymer has a detrimental impact. • A compromise polymer thickness increases ethylene yield and electrode stability. [ABSTRACT FROM AUTHOR]