Aqueous Zn-ion batteries have attracted increasing research interest; however, the development of these batteries has been hindered by several challenges, including dendrite growth, Zn corrosion, cathode material degradation, limited temperature adaptability and electrochemical stability window, which are associated with water activity and the solvation structure of electrolytes. Here we report that water activity is suppressed by increasing the electron density of the water protons through interactions with highly polar dimethylacetamide and trimethyl phosphate molecules. Meanwhile, the Zn corrosion in the hybrid electrolyte is mitigated, and the electrochemical stability window and the operating temperature of the electrolyte are extended. The dimethylacetamide alters the surface energy of Zn, guiding the (002) plane dominated deposition of Zn. Molecular dynamics simulation evidences Zn2+ ions are solvated with fewer water molecules, resulting in lower lattice strain in the NaV3O8·1.5H2O cathode during the insertion of hydrated Zn2+ ions, boosting the lifespan of Zn|| NaV3O8·1.5H2O cell to 3000 cycles.

Detection of a distinct ferromagnetic order at surfaces of Ni-Al solid solutions is reported. By monitoring Lorentz force induced attenuation of the low-energy Auger electron spectrum, the Curie temperature at the annealed Ni-9% Al(110) clean surface has been found 111 K higher than the bulk value, and for Ni-5% Al the enhancement is 58 K. Its origin and the induced attenuation effects are discussed. Ar bombardment or O 2 adsorption shift gradually the surface related transition temperature towards the bulk value.

Aluminum surface segregation in Ni-9% Al as studied by low-energy Auger electron spectroscopy is characterized by quite low equilibrium levels that increase with temperature, in contrast to predictions of Bragg-Williams-type theories. The free-energy cumulant expansion approach, adapted for surface segregation, reveals that short-range order can induce significant suppression of solute segregation, depending mainly on the solvent-solute interaction strength. The diminution of the effect with increasing temperature leads to anomalous increase of equilibrium segregation, in agreement with the Ni-Al experiments.

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