A novel MWCNT/nanotubular TiO2(B) loaded with SnO2 nanocrystals ternary composite as anode material for lithium-ion batteries

A novel MWCNT/long nanotubular TiO 2 (B) loaded with SnO 2 nanocrystals (SnO 2 NC/TiO 2 (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 TiO 2 (B) nanosheets, leading to the formation of TiO 2 (B) nanotubes with a length of ~9 μm. Among the SnO 2 NC/TiO 2 (B)NT/MWCNT composite, the wrapping and mechanical supporting functions of TiO 2 (B) nanotubes can effectively avoid the pulverization and aggregation of SnO 2 nanocrystals (SnO 2 NC) in lithium-ion charging and discharging process. Moreover, the synergistic effects of nanotubular TiO 2 (B) coating layer and three-dimensional interconnected network structure composed of TiO 2 (B) nanotubes and MWCNT were taken to mitigate volume expansion of SnO 2 NC and improve the transport of lithium ion and electron in the network. Tested as anode materials, the SnO 2 NC/TiO 2 (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 SnO 2 as anode material.