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Low cycling stability is one of the most crucial issues in rechargeable batteries. Herein, we study the effects of a simple ultrasound treatment of graphite for the reversible (de)intercalation of a ClO4− anion from a 2.4 M Al(ClO4)3 aqueous solution. We demonstrate that the ultrasound-treated graphite offers the improved reversibility of the ClO4− anion (de)intercalation compared with the untreated samples. The ex situ and in situ Raman spectroelectrochemistry and X-ray diffraction analysis of the ultrasound-treated materials shows no change in the interlayer spacing, a mild increase in the stacking order, and a large increase in the amount of defects in the lattice accompanied by a decrease in the lateral crystallite size. The smaller flakes of the ultrasonicated natural graphite facilitate the improved reversibility of the ClO4− anion electrochemical (de)intercalation and a more stable electrochemical performance with a cycle life of over 300 cycles.

Surface treatment of zinc galvanized steel is carried out usually using chromate based baths. These baths are used for improvement of the corrosion resistance and enhancement of the chemical adhesion of organic coatings. Anticorrosive effects of the chromium conversion coatings were not completely exceeded yet by another kind of passivation. Toxicity of CrVI is a basic problem of chromate conversion coats. This paper presents the main results and conclusions of experimental study on zinc conversion layers based on vanadates, using a good CrVI bath as reference. Anticorrosive mechanisms were compared by the corrosion tests in saline cabinet. Inhibition effects were characterized by scanning electron microscopy, by X-ray dispersive spectrometry (EDS) associated X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy.

This work attempts to understand the behaviour of Ge-induced cytotoxicity of germanium-doped hydrogen-free diamond-like carbon (DLC) films recently thoroughly studied and published by Jelinek et al. At a low doping level, the films showed no cytotoxicity, while at a higher doping level, the films were found to exhibit medium to high cytotoxicity. We demonstrate, using surface-sensitive methods—two-angle X-ray-induced core-level photoelectron spectroscopy (ARXPS) and Low Energy Ion Scattering (LEIS) spectroscopy, that at a low doping level, the layers are capped by a carbon film which impedes the contact of Ge species with tissue. For higher Ge content in the DLC films, oxidized Ge species are located at the top surface of the layers, provoking cytotoxicity. The present results indicate no threshold for Ge concentration in cell culture substrate to avoid a severe toxic reaction.