Scanning transmission electron microscopy (STEM) data with atomic resolution can contain a large amount of information about the structure of a crystalline material. Often, this information is hard to extract, due to the large number of atomic columns and large differences in intensity from sublattices consisting of different elements. In this work, we present a free and open source software tool for analysing both the position and shapes of atomic columns in STEM-images, using 2-D elliptical Gaussian distributions. The software is tested on variants of the perovskite oxide structure. By first fitting the most intense atomic columns and then subtracting them, information on all the projected sublattices can be obtained. From this, we can extract changes in the lattice parameters and shape of A-cation columns from annular dark field images of perovskite oxide heterostructures. Using annular bright field images, shifts in oxygen column positions are also quantified in the same heterostructure. The precision of determining the position of atomic columns is compared between STEM data acquired using standard acquisition, and STEM-images obtained as an image stack averaged after using non-rigid registration.

In this work, silicon/carbon composites for anode electrodes of Li-ion batteries are prepared from Elkem’s Silgrain® line. Gentle ball milling is used to reduce particle size of Silgrain, and the resulting Si powder consists of micrometic Si with some impurities. Silicon/carbon composite with CMC/SBR as a dual binder can achieve more than 1200 cycles with a capacity of 1000 mAh g−1 of Si. This excellent electrochemical performance can be attributed to the use of a buffer as a solvent to control the pH of the electrode slurry, and hence the bonding properties of the binder to the silicon particles. In addition, the use of FEC as an electrolyte additive is greatly contributing to a stabilized cycling by creating a more robust SEI layer. This work clearly demonstrates the potential of industrial battery grade silicon from Elkem.

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The many outstanding properties of graphene have impressed and intrigued scientists for the last few decades. Its transparency to light of all wavelengths combined with a low sheet resistance makes it a promising electrode material for novel optoelectronics. So far, no one has utilized graphene as both the substrate and transparent electrode of a functional optoelectronic device. Here, we demonstrate the use of double-layer graphene as a growth substrate and transparent conductive electrode for an ultraviolet light-emitting diode in a flip-chip configuration, where GaN/AlGaN nanocolumns are grown as the light emitting structure using plasma-assisted molecular beam epitaxy. Although the sheet resistance is increased after nanocolumn growth compared with pristine double-layer graphene, our experiments show that the double-layer graphene functions adequately as an electrode. The GaN/AlGaN nanocolumns are found to exhibit a high crystal quality with no observable defects or stacking faults. Room temperature electroluminescence measurements show a GaN related near bandgap emission peak at 365 nm and no defect-related yellow emission.

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LaCoO 3 -materials have received considerable attention due to their novel magnetic properties [1][2][3] and mixed ionicelectronic conductivity at elevated temperatures leading to exciting applications such as electrodes in solid oxide fuel cells [4] and oxygen permeable membranes.[5] Perovskites such as LaCoO 3 and related materials like LaAlO 3 undergo a displacive phase transition from a paraelastic cubic perovskite with space group Pm 3m at high temperatures to a ferroelastic rhombohedral perovskite with space group R 3c. [6][7][8][9][10] Toughening of the materials is particularly beneficial for membrane applications. Ferroelastic domain switching in LaCoO 3 -materials under mechanical load may increase the fracture toughness of the materials.[11] Microstructure investigations of the ferroelastic domains and switching mechanisms in LaCoO 3 -materials are therefore interesting in order to understand the materials′ mechanical behavior. In this work we report a detailed transmission electron microscopy (TEM) analysis of the ferroelastic domains in LaCoO 3 -based materials. In addition to the well known ferroelastic domains formed by deformation twinning in rhombohedral perovskites, a monoclinic structure is observed by TEM in LaCoO 3 -based materials. The second order improper paraelastic to ferroelastic phase transition in LaCoO 3 -materials doubles the periodicity along the threefold axis, which becomes the unique axis of the rhombohedral ferroelastic state. The phase transition results in the well known deformation twinning (ferroelastic twin domain [12]

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