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Aluminum batteries (ABs) have been considered as a viable candidate for new‐generation energy‐storage devices due to its low cost and high theoretical volumetric capacity. Despite these advantages, the large‐scale application of ABs is constrained by scarce options of suitable cathode materials. Herein, three‐dimensional nanostructured α‐MnSe microspheres with porous properties are reported as a cathode for ABs. The nanosized and porous structure of α‐MnSe could offer numerous open channels and the short ionic transport path, which would efficiently mitigate volume changes and enhance electrochemical reaction kinetics. Moreover, the pseudocapacitive characteristic of Al3+ storage in α‐MnSe contributes to the fast kinetics of the cathode. It is demonstrated that the reversible Al3+ insertion/extraction occurs in the α‐MnSe cathode during the cycling process. The resulting aluminum battery based on the α‐MnSe cathode, AlCl3/[EMIm]Cl ionic liquid electrolyte, and aluminum anode exhibits an ultrahigh reversible capacity of 408 mA h g−1 at 0.2 A g−1. Even for a current density at 1 A g−1, a discharge capacity of 131 mA h g−1 could be retained with a Coulombic efficiency of 97 % over 150 cycles. This strategy has referential significance in aspects of the selection of compatible cathode for ABs. [ABSTRACT FROM AUTHOR]

The partitioning behaviors of alloying elements Cr, Co, Al, Ta, etc. on the γ and γ′ phases of high Cr-containing (∼9wt.%) nickel-base single crystal superalloys have been investigated with and without the addition of 3wt.% Ru. The “reverse partitioning effect” occurs, which means that the addition of Ru causes the partition of Cr and Co into γ′ phase, while Al an Ta concentrate into γ matrix. However, Ru promotes the precipitation of topologically close-packed (TCP) phases, since the diffusion coefficient between the TCP phase and the matrix interface increases with the diffusion behaviors of refractory elements. For the coarsening and slightly rafting of γ′ phases, the increase of elemental diffusion plays much more important role in its kinetic process than the decrease of lattice misfit. [ABSTRACT FROM AUTHOR]

Here, we investigate a new type of kink structure that is found at γ/γ′ interfaces in nickel-based single crystal superalloys. We studied these structures at the atomic and elemental level using aberration corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The core of the dislocation absorbs high-Z elements (i.e., Co and Re) that adopt hexagonal arrangements, and it extrudes elements (i.e., Ni and Al) that adopt face centered cubic (fcc) structures. High-Z elements (i.e., Ta and W) and Cr, which is a low-Z element, are stabilized in body centered cubic (bcc) arrangements; Cr tends to behave like Re. High-Z elements, which migrate and adopt a hexagonal structure, induce kink formation at γ/γ′ interfaces. This process must be analyzed to fully understand the kinetics and dynamics of creep in nickel-based single crystal superalloys. [ABSTRACT FROM AUTHOR]