TiO2 nanocrystal embedded ordered mesoporous carbons as anode materials for lithium-ion batteries with highly reversible capacity and rate performance

Abstract

The ordered mesoporous carbon/TiO2 (OMCT) nanocomposites with TiO2 nanocrystals embedded within ordered mesoporous carbon (OMC) were prepared by a simple solvothermal method. The effect of TiO2 nanoparticle incorporation in OMC matrix on the mesoporous structure, pore size, pore volume, surface area and microstructure of OMCT composites was investigated using X-ray diffraction, N2 adsorption–desorption and Brunauer–Emmett–Teller method, scanning electron microscopy and transmission electron microscopy. The electrochemical lithium storage capacities of OMCT composites with different incorporated TiO2 nanoparticles are comparatively investigated using cyclic voltammetry and galvanostatic charge–discharge techniques. It is suggested that the OMCT composites as anode materials for lithium ion batteries display a greatly improved electrochemical performance with high reversible capacity, coulombic efficiency, rate capability and cycling performance. As an anode electrode for Li-ion battery, OMCT15 composite with an incorporated TiO2 nanocrystal content possesses a high reversible capacity of 540.9 mA h g−1 even up to 60 cycles at a high current density of 100 mA g−1, with a stable coulombic efficiency of 98% and good rate capability. Especially at the current density of 1600 mA g−1 after 50 cycles, the reversible capacity of the OMCT15 remains at a value of 260 mA h g−1, 5 times that of the OMC (48.9 mA h g−1) and 21 times that of the pure TiO2 (12.4 mA h g−1) electrodes, respectively. The improved electrochemical lithium storage performance of high reversible capacity, coulombic efficiency, rate performance and cycling ability can be mainly attributed to the synergic effects between the TiO2 nanoparticles and the three dimensional OMC matrices.