Rechargeable aluminum-ion batteries (AIBs) possess significant advantages of high energy density, safety performance, and abundant natural resources, making them one of the desirable next-generation substitutes for lithium battery systems. However, the poor reversibility, short lifespan, and low capacity of positive materials have limited its practical applications. In comparison with semiconductors, the metallic nickel telluride (NiTe) alloy with enhanced electrical conductivity and fast electron transmission is a more favorable electrode material that could significantly decrease the kinetic barrier during battery operation for energy storage. In this paper, the NiTe nanorods prepared through a simple hydrothermal routine enable an initial reversible capacity of approximately 570 mA h g-1 (under the current density of 200 mA g-1) to be delivered on the basis of the ionic liquid electrolyte, along with the average voltage platform of about 1.30 V. Moreover, the cycling performance could be easily enhanced using a modified separator to prevent the diffusion of soluble intermediate species to the negative electrode side. At a high rate of 500 mA g-1, the NiTe nanorods could retain a specific capacity of about 307 mA h g-1 at the 100th cycle. The results have important implications for the research of transition metal tellurides as positive electrode materials for AIBs.
Keywords: aluminum-ion batteries; cycling performance; high capacities; positive electrodes; transition metal tellurides.