Rational design of coaxial cable MoSe2/C: Towards high performance electrode materials for lithium ion and sodium ion batteries
Abstract A novel coaxial cable MoSe2/hollow carbon nanofiber composites (denoted as coaxial cable MoSe2/C composites) is fabricated employing selenium/carbon core shell composite as the template, carbon and selenium resource. Hollow carbon nanofibers are uniformly decorated with few layered and ultrasmall MoSe2 nanosheets by the observation of TEM. When calculated on the basis of the whole composite, coaxial cable MoSe2/C composites not only show high lithium specific capacity (658 mAh g 1) and excellent cycling performance (almost 100% capacity retention even after 100 cycles at a current density of 0.5 A g 1) but also exhibit a high rate capability of 524 mAh g 1 at the rate of 3 A g 1. When evaluated as an anode for sodium storage, a specific capacity of 423 mAh g 1and 395 mAh g 1 is achieved at 0.5 A g 1 and 1 A g 1 after 100 cycles, respectively. Excellent cycling stability and rate performance of the coaxial cable MoSe2/C composites can be ascribed to the synergic effects of few layered and ultrasmall MoSe2 nanosheets as well as hollow carbon nanofibers. Our study not only provides a facile synthetic method for both lithium ion and sodium ion batteries, but also exploits a novel way to the combination of Se based compounds and carbon matrix.