Confinement Growth of Layered WS 2 in Hollow Beaded Carbon Nanofibers with Synergistic Anchoring Effect to Reinforce Li + /Na + Storage Performance

Novel nitrogen doped (N‐doped) hollow beaded structural composite carbon nanofibers are successfully applied for lithium‐ion batteries (LIBs) and sodium‐ion batteries (SIBs). Tungsten disulfide (WS 2 ) nanosheets are confined, through synergistic anchoring, on the surface and inside of hollow beaded carbon nanofibers (HB CNFs) via a hydrothermal reaction method to construct the hierarchical structure HB WS 2 @CNFs. Benefiting from this unique advantage, HB WS 2 @CNFs exhibits remarkable lithium‐storage performance in terms of high rate capability (≈351 mAh g −1 at 2 A g −1 ) and stable long‐term cycle (≈446 mAh g −1 at 1 A g −1 after 100 cycles). Moreover, as an anode material for SIBs, HB WS 2 @CNFs obtains excellent long cycle life and rate performance. During the charging/discharging process, the evolution of morphology and composition of the composite are analyzed by a set of ex situ methods. This synergistic anchoring effect between WS 2 nanosheets and HB CNFs is capable of effectively restraining volume expansion from the metal ions intercalation/deintercalation process and improving the cycling stability and rate performance in LIBs and SIBs.