Few-Layered ReS2@CNTs as a High-Performance Cathode for Aluminum-Ion Batteries

With a high theoretical specific capacity of 2978 mAh g(-1), rechargeable aluminum-ion batteries (AIBs) are considered as promising next-generation energy storage devices with higher electrochemical performance. Nevertheless, the search for stable cathode materials with outstanding capacity and rate performance remains elusive. In current work, few-layered ReS2 is in situ grown on carbon nanotubes (CNTs) to form the ReS2@CNTs composite. As ReS2 features a large interlayer spacing of approximate to 0.65 nm, the extremely weak interlayer coupling can effectively reduce the electrostatic repulsion between Al3+ ions and the cathode host, adequately accommodating large amounts of Al3+ ions without significant volume expansion. When it serves as the cathode in the AIB, ReS2@CNTs delivers a high discharge specific capacity of 396.3 mA h g(-1) and Coulombic efficiencies of approximate to 100% both after 250 cycles at a low rate (200 mA g(-1)) and 10 000 cycles under a higher rate (1 A g(-1)). Theoretical simulations and ex situ grazing incidence angle X-ray diffraction results reveal that Al3+ cations can be favorably and reversibly intercalated/deintercalated into the ReS2@CNTs during the discharge/charge process. This work provides new insights into AIB chemistry and paves the way for the development of high-performance AIBs.