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In the realm of advanced anode materials for lithium-ion batteries, this study explores the electrochemical performance of a high-entropy oxide (HEO) with a unique spinel structure. The equiatomic composition of CrMnFeCoCu was synthesized and subjected to a comprehensive materials characterization process, including X-ray diffraction and microscopy techniques. The multicomponent alloy exhibited a multiphase structure, comprising two face-centered cubic (FCC) phases and an oxide phase. Upon oxidation, the material transformed into a spinel oxide with a minor presence of CuO. The resulting high-entropy oxide demonstrated excellent electrochemical behavior when utilized as an anode material. Cyclic voltammetry revealed distinctive reduction peaks attributed to cation reduction and solid electrolyte interphase (SEI) layer formation, while subsequent cycles showcased high reversibility. Electrochemical impedance spectroscopy indicated a decrease in charge transfer resistance during cycling, emphasizing the remarkable electrochemical performance. Galvanostatic charge/discharge tests displayed characteristic voltage profiles, with an initial irreversible capacity attributed to SEI layer formation. The HEO exhibited promising rate capability, surpassing commercial graphite at higher current densities. The battery achieved 80% (275 mAh g−1) of its initial stable capacity at a current density of 500 mA g−1 by the 312th cycle. Post-mortem analysis revealed structural amorphization during cycling, contributing to the observed electrochemical behavior. This research highlights the potential of HEOs as advanced anode materials for lithium-ion batteries, combining unique structural features with favorable electrochemical properties. [ABSTRACT FROM AUTHOR]

A new crystal structure of catena-(bis((µ4-cubane-1,4-dicarboxylato)-(N-methyl-2-pyrrolidone)-zinc(II)) N-methyl-2-pyrrolidone solvate) (1) was prepared by solvothermal method. The crystal structure of the compound was analyzed by single-crystal X-ray diffraction. It has a P1 space group, with lattice parameters a = 10.7190(4) Å, b = 10.8245(5) Å, c = 10.8403(8) Å, a = 80.291(5)°, ß = 70.0015(5)°, γ = 77.531(4)°, V = 1147.97(12) ų. The secondary building units of 1 consist of 2 central Zn ions, coordinated by 4 carboxylate groups in a bis-monodentate way, forming a square planar configuration of Zn2(CO2)4, known as paddle-wheel units. The paddle-wheels are connected by cubane-1,4-dicarboxylic acid linkers at the edges, resulting in a two-dimensional coordination polymer with a square lattice (sql) underlying network topology. The axial sites of the zinc atoms are occupied by N-methyl-2-pyrrolidone molecules. In this new crystal structure the two-dimensional polymer planes are interstacked by weak dispersion bonds. The axial N-methyl- 2-pyrrolidone solvent molecules determine the distances of planar polymer planes. The thermal properties of this new structure were studied by thermogravimetry/mass spectrometry in inert atmosphere. It was found, that the organic linkers in the framework structure do not decompose below 200 °C. The stochiometry of the activated compound is Zn2[C8H6(COO)2]2(C5H9NO)2, as determined by thermogravimetry in oxidative atmosphere. [ABSTRACT FROM AUTHOR]

Solvent-free Sc3N@C80-Ihwas prepared for the first time in high quality microcrystalline form via thermal decomposition of its toluene cocrystal. The production route and structural studies of both materials are presented. The structures were determined by x-ray powder diffraction, and confirmed by cohesion energy calculations. The solvent-free endohedral fullerene forms face centered cubic crystals with lattice parametera= 15.611 Å and the molecules are orientationally disordered. This is a new member of the high-symmetry isostructural expansion series of fullerenes. The parent cocrystals precipitated from toluene possess 1:1 stoichiometry; their structure is orthorhombic ofCmcmspace-group. At room temperature the toluene molecules are located in large cavities in a severely disordered way. A symmetry lowering phase transition is observed on cooling indicating the dynamic nature of the disorder. The decomposition, assisted by toluene diffusion at elevated temperatures, is also analyzed in detail. [ABSTRACT FROM AUTHOR]

In coherent-diffraction-imaging experiments X-ray diffraction patterns of identical particles are recorded. The particles are injected into the X-ray free-electron laser (XFEL) beam in random orientations. If the particle has symmetry, finding the orientation of a pattern can be ambiguous. With some modifications, the correlation-maximization method can find the relative orientations of the diffraction patterns for the case of symmetric particles as well. After convergence, the correlation maps show the symmetry of the particle and can be used to determine the symmetry elements and their orientations. The C factor, slightly modified for the symmetric case, can indicate the consistency of the assembled three-dimensional intensity distribution.

The short pulses of X-ray free-electron lasers can produce diffraction patterns with structural information before radiation damage destroys the particle. From the recorded diffraction patterns the structure of particles or molecules can be determined on the nano- or even atomic scale. In a coherent diffraction imaging experiment thousands of diffraction patterns of identical particles are recorded and assembled into a three-dimensional distribution which is subsequently used to solve the structure of the particle. It is essential to know, but not always obvious, that the assembled three-dimensional reciprocal-space intensity distribution is really consistent with the measured diffraction patterns. This paper shows that, with the use of correlation maps and a single parameter calculated from them, the consistency of the three-dimensional distribution can be reliably validated.