CNTs–C@TiO 2 composites with 3D networks as anode material for lithium/sodium ion batteries

CNTs–C@TiO 2 composite with 3D networks as electrode has been synthesized for lithium ion batteries (LIBs)/sodium ion batteries (SIBs) by a traditional solvothermal process. The composites were characterized by scanning electron microscopy, field emission electron microscopy, X-ray diffraction, Raman spectroscopy, thermogravimetric analysis, and X-ray photoelectron spectroscopy. The continuous 3D conductive networks, which consisted of acid-treated CNTs, provided numerous attachment sites for TiO 2 particles and carbon layers (similar to a shell) produced by the Ti 4+ -induced polymerization of ethylene glycol, thereby promoting electron and ion transfer. The composites contained 10.09 wt% CNTs (excellent conductor) and 12.75 wt% pyrolytic carbon. The Raman spectra confirmed the high degree of graphitization of the composites, and the improved conductivity resulted in outstanding electrochemical behavior. The electrochemical performance in the Li + /Na + storage of CNTs–C@TiO 2 composites was greatly enhanced, as revealed by this material’s outstanding capacity of 205 mA h g −1 at a current density of 0.1 A g −1 after 200 scanning cycles for LIBs and 148 mA h g −1 at 0.1 A g −1 over 100 cycles for SIBs.