Free-standing N-doped hollow carbon fiber encapsulate P/GeP hybrid anode for rechargeable Li-ion battery

Red phosphorus (RP) with appropriate working voltage and high lithium storage specific capacity has been considered as high-performance anode for Li-ion battery (LiB). However, the volume expansion of the RP anode reached 350 % during the intercalation/deintercalation of Li-ion processes, resulting in the detachment of active material and poor specific capacity. Herein, flexible hollow nanochannel carbon nanofiber was prepared through simple electrospinning, then P/GeP nano powder were encapsulated in the N-rich carbon nanofiber using a facile in situ synthesis method, where the introduction of GeP not only innovatively served as the high conductive dispersant for P, but simultaneously acted as the active component in reacting with Li-ion. The unique designed nanoarchitecture not only boosted the structural stability and electronic conductivity of the hybrid composite, but also facilitated the transport of electrons and Li-ion. Upon served as free-standing LiB anode, the N-doped hollow carbon fiber encapsulate P/GeP (P/GeP/C) anode displayed remarkably reversible capacities, superior rate performances, and long-term cycle stability for lithium storage. For instance, P/GeP/C of only 10.6 wt% GeP and 28.5 wt% P delivered 290.2 mA h g−1 under a high current density of 5 A g−1 and showed a high capacity of 575.6 and 436.9 mA h g−1 at a current density of 0.1 A g−1 and 1.0 A g−1 after 50 cycles, respectively.