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The prospective applications of metallic glasses are limited by their lack of ductility, attributed to shear banding inducing catastrophic failure. A concise depiction of the local atomic arrangement (local atomic packing and chemical short‐range order), induced by shear banding, is quintessential to understand the deformation mechanism, however still not clear. An explicit view of the complex interplay of local atomic structure and chemical environment is presented by mapping the atomic arrangements in shear bands (SBs) and in their vicinity in a deformed Vitreloy 105 metallic glass, using the scanning electron diffraction pair distribution function and atom probe tomography. The results experimentally prove that plastic deformation causes a reduction of geometrically favored polyhedral motifs. Localized motifs variations and antisymmetric (bond and chemical) segregation extend for several hundred nanometers from the SB, forming the shear band affected zones. Moreover, the variations within the SB are found both perpendicular and parallel to the SB plane, also observable in the oxidation activity. The knowledge of the structural–chemical changes provides a deeper understanding of the plastic deformation of metallic glasses especially for their functional applications and future improvements.

For decades, scanning/transmission electron microscopy (S/TEM) techniques have been employed to analyze shear bands in metallic glasses and understand their formation in order to improve the mechanical properties of metallic glasses. However, due to a lack of direct information in reciprocal space, conventional S/TEM cannot characterize the local strain and atomic structure of amorphous materials, which are key to describe the deformation of glasses. For this work, 4‐dimensional‐STEM (4D‐STEM) is applied to map and directly correlate the local strain and the atomic structure at the nanometer scale in deformed metallic glasses. Residual strain fields are observed with quadrupolar symmetry concentrated at dilated Eshelby inclusions. The strain fields percolate in a vortex‐like manner building up the shear band. This provides a new understanding of the formation of shear bands in metallic glass.

The hampered kinetics of reactive hydride composites (RHCs) in hydrogen storage and release, which limits their use for extensive applications in hydrogen storage S1and energy conversion, can be improved using additives. However, the mechanism of the kinetic restriction and the additive effect on promoting the kinetics have remained unclear. These uncertainties are addressed by utilizing versatile transmission electron microscopy (TEM) on the LiBH₄-MgH₂ composite under the influence of the 3TiCl₃·AlCl₃ additives. The formation of the MgB₂ phase, as the rate-limiting step, is emphatically studied. According to the observations, the heterogeneous nucleation of MgB₂ relies on different nucleation centers (Mg or TiB₂ and AlB₂). The varied nucleation and growth of MgB₂ are related to the in-plane strain energy density at the interface, resulting from the atomic misfit between MgB₂ and its nucleation centers. This leads to distinct MgB₂ morphologies (bars and platelets) and different performances in the dehydrogenation kinetics of LiBH₄-MgH₂. It was found that the formation of numerous MgB₂ platelets is regarded as the origin of the kinetic improvement. Therefore, to promote dehydrogenation kinetics in comparable RHC systems for hydrogen storage, it is suggested to select additives delivering a small atomic misfit.

As promising cathode materials, the lithium-excess 3d-transition-metal layered oxides can deliver much higher capacities (>250 mAh g−1 at 0.1 C) than the current commercial layered oxide materials (≈180 mAh g−1 at 0.1 C) used in lithium ion batteries. Unfortunately, the original formation mechanism of these layered oxides during synthesis is not completely elucidated, that is, how is lithium and oxygen inserted into the matrix structure of the precursor during lithiation reaction? Here, a promising and practical method, a coprecipitation route followed by a microwave heating process, for controllable synthesis of cobalt-free lithium-excess layered compounds is reported. A series of the consistent results unambiguously confirms that oxygen atoms are successively incorporated into the precursor obtained by a coprecipitation process to maintain electroneutrality and to provide the coordination sites for inserted Li ions and transition metal cations via a high-temperature lithiation. It is found that the electrochemical performances of the cathode materials are strongly related to the phase composition and preparation procedure. The monoclinic layered Li[Li0.2Ni0.2Mn0.6]O2 cathode materials with state-of-the-art electrochemical performance and comparably high discharge capacities of 171 mAh g−1 at 10 C are obtained by microwave annealing at 750 °C for 2 h.