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State-of-the-art scanning probe microscopy (SPM) methods as applied to energy conversion and storage devices, specifically lithium-ion batteries, are reviewed with an emphasis on the electroactive elements. The unique ability of SPM-based methods to provide localized information has proven highly valuable for the in-depth understanding of the fundamental mechanisms, processes, and degradation of lithium-ion batteries (LIBs). As such, SPM analysis is poised to play a strong role in the competition for new higher performing LIBs, especially given the unprecedented choice and availability of SPM techniques tailored to provide physical and chemical information at the nanoscale. [ABSTRACT FROM AUTHOR]

The article offers information on the recent trends in scanning probe techniques that are useful in understanding magnesium alloy corrosion.

The uptake of menadione (2-methyl-1,4-naphthoquinone), which is toxic to yeast cells, and its expulsion as a glutathione complex were studied by scanning electrochemical microscopy. The progression of the in vitro reaction between menadione and glutathione was monitored electrochemically by cyclic voltammetry and correlated with the spectroscopic (UV-visible) behavior. By observing the scanning electrochemical microscope tip current of yeast cells suspended in a menadione-containing solution, the export of the conjugate from the cells with time could be measured. Similar experiments were performed on immobilized yeast cell aggregates stressed by a menadione solution. From the export of the menadione-glutathione conjugate detected at a 1-μm-diameter electrode situated 10 μm from the cells, a flux of about 30,000 thiodione molecules per second per cell was extracted. Numerical simulations based on an explicit finite difference method further revealed that the observation of a constant efflux of thiodione from the cells suggested the rate was limited by the uptake of menadione and that the efflux through the glutathione-conjugate pump was at least an order of magnitude faster. [ABSTRACT FROM AUTHOR]

The Back Cover picture represents a paper in which scanning probe microscopy methods applied to energy conversion and storage devices (specifically lithium‐ion batteries) are reviewed, with an emphasis on the electroactive elements. More information can be found in the Review by S. B. Schougaard, J. Mauzeroll, and co‐workers on page 6 in Issue 1, 2017 (DOI: 10.1002/celc.201600571). [ABSTRACT FROM AUTHOR]

In scanning electrochemical microscopy (SECM), an approach curve performed in feedback mode involves the downward displacement of a microelectrode toward a substrate while applying a bias to detect dissolved electroactive species at a diffusion-limited rate. The resulting measured current is said to be at steady state. In order to reduce the required measurement time, the approach velocity can be increased. In this paper, we investigate experimentally and theoretically the combination of diffusion and convection processes related to a moving microdisk electrode during feedback approaches. Transient modeling and numerical simulations with moving boundaries are performed, and the results are compared to the experimental approach curves obtained in aqueous solution. The geometry and misalignment of the microelectrode influence the experimental approach curves recorded at high approach velocities. The effects are discussed through the decomposition of the current into transient diffusional, radial convectional, and axial convectional contributions. Finally a ready-to-use expression is provided to rapidly evaluate the maximal approach velocity for steady state measurements as a function of the microelectrode geometry and the physical properties of the media. This expression holds for the more restrictive case of negative feedback as well as other modes, such as SECM approach curves performed at substrates displaying first order kinetics. [ABSTRACT FROM AUTHOR]

The present work uses a scanning electrochemical microscopy technique to study systems containing the membrane-bound reaction center protein (RC) from the purple photosynthetic bacteria Rhodobacter spheroides to chromatophores (spherical reorganization of cell membrane following its mechanical rupture) and liposomes (reconstituted membrane systems at lower degree of complexity). Scanning electrochemical microscopy is a useful tool to investigate redox processes involving a RC, because the effective heterogeneous rate constants for the redox reaction with different mediators can be measured. The technique is also able to provide information on the role of the outer cell membrane permeation on the kinetics of the electron-transfer processes and to obtain more insight into the nature of the species involved. [ABSTRACT FROM AUTHOR]