The variation in the high temperature thermodynamic properties of the Li-Sb system with temperature (425-775 o C) and composition (x Li = 0.01-0.75) was determined by electromotive force (emf) measurements in a cell configured as follows: Li-Bi reference electrode (x Bi = 0.35) | eutectic of LiCl-KCl or LiCl-LiF | Li-Sb alloy. On the basis of these data the Li-Sb couple was deemed attractive for storage of electrical energy in a liquid metal battery. In addition, an updated Li-Sb binary phase diagram is proposed. © The Author(s) 2014. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. [DOI: 10.1149/2.0671503jes] All rights reserved. The lithium-antimony (Li-Sb) binary system is of interest for energy storage applications, specifically at high temperatures for liquid metal batteries, because of the mutual reactivity of these elements, their relative abundance in the earth's crust, and their comparatively low cost.1,2 Prior investigations of this system are limited and are generally focused on intermetallic characterization.3-5 Notably, two groups have studied the intermetallics Li 2 Sb(s) and Li 3 Sb(s) electrochemically, determining the thermodynamic electric potential and Gibbs free energy of formation of the compounds between 355 o C and 600 o C. 3,6,7 As for liquid alloys, Nikitin et al. 3 studied the deposition of lithium by cathodic polarization of liquid antimony and observed that electrode potential varied inversely with both current density and degree of lithiation, which they attributed to formation of composition gradients.In 1993 Sangster and Dalton presented a calculated Li-Sb phase diagram; 4 however, for liquid interactions they relied on data from the Li-Bi system due to a perceived lack of thermodynamic data for Li-Sb liquid alloys. Two years later Fedorov 8 published an alternate version of the Li-Sb phase diagram determined from cooling curves (cooling rate unknown), specifying that it was a non-equilibrium phase diagram, an opinion expressed by others. 9In the present study electromotive force (emf) measurements characterize the thermodynamic properties of Li in Li-Sb liquid alloys between 425 o C and 775 o C. Emf measurements have been used to accurately characterize similar lithium binary systems in the past. 10-14The Li-Sb system was studied in this work using the electrochemical cellwhere a Li-Bi two phase alloy served as the reference electrode (RE), the Li-Sb alloys of various concentrations served as the working electrode (WE), and either of the two eutectic binary molten salts as the electrolyte. The half cell reactions of this cell areand the full cell reaction iswhere the parentheses indicate the solvent metal. The open circuit potential (OCP) at equilibrium E cell is related to the Gibbs free energy of reaction r G via the Nernst equationwhere n is the ...

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Complex ferromagnetic oxides have been identified as possible candidate materials for sources of spin currents. Here we study bilayers of ferromagnetic (La2/3Sr1/3)MnO3 (LSMO) and metallic CaRuO3 (CRO) on LSAT substrates as a model system for spin pumping. Ferromagnetic resonance (FMR) measurements of these bilayers show evidence of spin pumping across the interface in the form of an increase in Gilbert damping with the addition of CRO. FMR indicates that the presence of CRO modifies the magnetic anisotropy of the LSMO. By increasing CRO thickness, we find a reduction of the out-of-plane anisotropy and simultaneous rotation of the easy axis within the plane, from the ⟨110⟩ to ⟨100⟩ axis. The evolution of magnetic anisotropy determined by FMR disagrees with that measured by bulk SQUID magnetometry and is accompanied by structural distortions in the LSMO layer as measured by x-ray diffraction, thus suggesting a change in magnetic anisotropy attributed to structural distortions imposed on LSMO by CRO. These results suggest that while LSMO and CRO remain promising candidates for efficient pure spin current generation and detection, respectively, epitaxial integration of perovskites will cause additional changes which must be accounted for in spintronics applications.

The emergence of ferromagnetism in materials where the bulk phase does not show any magnetic order demonstrates that atomically precise films can stabilize distinct ground states and expands the phase space for the discovery of materials. Here, the emergence of long-range magnetic order is reported in ultrathin (111) LaNiO3 (LNO) films, where bulk LNO is paramagnetic, and the origins of this phase are explained. Transport and structural studies of LNO(111) films indicate that NiO6 octahedral distortions stabilize a magnetic insulating phase at the film/substrate interface and result in a thickness-dependent metal–insulator transition at t = 8 unit cells. Away from this interface, distortions relax and bulk-like conduction is regained. Synchrotron x-ray diffraction and dynamical x-ray diffraction simulations confirm a corresponding out-of-plane unit-cell expansion at the interface of all films. X-ray absorption spectroscopy reveals that distortion stabilizes an increased concentration of Ni2+ ions. Evidence of long-range magnetic order is found in anomalous Hall effect and magnetoresistance measurements, likely due to ferromagnetic superexchange interactions among Ni2+–Ni3+ ions. Together, these results indicate that long-range magnetic ordering and metallicity in LNO(111) films emerges from a balance among the spin, charge, lattice, and orbital degrees of freedom.