摘要
Interface engineering on 2D layered nanomaterials plays pivotal roles in achieving novel properties and superior device performance. In this work, hierarchical nanotubes consisting of 2D monolayer MoS2 and carbon (MoS2:C) interoverlapped superstructure nanosheets have been synthesized, in which the MoS2 and carbon layers are alternately sandwiched. The hierarchical architectures assembled from the MoS2:C superstructures are beneficial for: (i) providing substantially expanded (002) interlayer spacing (0.98 nm) of 2H-MoS2 which facilitates fast Na+ insertion/extraction reaction kinetics, (ii) improving electrical conductivity of MoS2 by carbon monolayer insertion with ideal heterointerface contact, (iii) preventing aggregation of MoS2 nanosheets, and (iv) accommodating volume change upon sodiation/desodiation. The superstructure nanotubes are demonstrated as a robust anode material for sodium storage with superior electrochemical performance. They deliver a high rate-capability and maintain discharge capacities of 295 and 187 mAh g(-1) at high current densities of 10.0 and 20.0 A g(-1), respectively. Furthermore, they show durable cycling life (capacity retention of 101.3%, 108.2% and 107.8% after 200 cycles at current densities of 0.2, 0.5 and 1.0 A g(-1), respectively, in comparison to those of the 2nd cycles), and an initial Coulombic efficiency as high as 84%. The MoS2:C superstructure nanotubes perform among the best of current MoS2-based electrode materials.
- 出版日期2016-4
- 单位合肥工业大学