Novel Insight into Rechargeable Aluminum Batteries with Promising Selenium Sulfide@Carbon Nanofibers Cathode
Linlin Li, Yanchen Ma, Fangyan Cui, Yan Li, Deshuang Yu, Xintong Lian, Yuxiang Hu, Hongyi Li, Shengjie Peng
Abstract
Abstract Due to the unique electronic structure of aluminum ions (Al 3+ ) with strong Coulombic interaction and complex bonding situation (simultaneously covalent/ionic bonds), traditional electrodes, mismatching with the bonding orbital of Al 3+ , usually exhibit slow kinetic process with inferior rechargeable aluminum batteries (RABs) performance. Herein, to break the confinement of the interaction mismatch between Al 3+ and the electrode, a previously unexplored Se 2.9 S 5.1 ‐based cathode with sufficient valence electronic energy overlap with Al 3+ and easily accessible structure is potentially developed. Through this new strategy, Se 2.9 S 5.1 encapsulated in multichannel carbon nanofibers with free‐standing structure exhibits a high capacity of 606 mAh g −1 at 50 mA g −1 , high rate‐capacity (211 mAh g −1 at 2.0 A g −1 ), robust stability (187 mAh g −1 at 0.5 A g −1 after 3,000 cycles), and enhanced flexibility. Simultaneously, in/ex‐situ characterizations also reveal the unexplored mechanism of Se x S y in RABs.