摘要

A novel MWCNT/long nanotubular TiO2(B) loaded with SnO2 nanocrystals (SnO2NC/TiO2(B)NT/MWCNT) ternary composite has been prepared by two-step hydrothermal method and used as the anode material for the first time. In this work, the mechanical stirring improved the diffusion and surface reaction rates of reactants and promoted the appearance of longer intermediate TiO2(B) nanosheets, leading to the formation of TiO2(B) nanotubes with a length of similar to 9 mu m. Among the SnO2NC/TiO2(B)NT/MWCNT composite, the wrapping and mechanical supporting functions of TiO2(B) nanotubes can effectively avoid the pulverization and aggregation of SnO2 nanocrystals (SnO2NC) in lithium-ion charging and discharging process. Moreover, the synergistic effects of nanotubular TiO2(B) coating layer and three-dimensional interconnected network structure composed of TiO2(B) nanotubes and MWCNT were taken to mitigate volume expansion of SnO2NC and improve the transport of lithium ion and electron in the network. Tested as anode materials, the SnO2NC/TiO2(B)NT/MWCNT composite maintained 211 mAh g(-1) at 3000 mA g(-1) after three testing processes with alternative current density of 200 and 3000 mA g(-1) and could rebound to 338 mAh g(-1) at a current density of 200 mA g(-1), indicating an effective way to optimize electrochemical properties of SnO2 as anode material.