2D black TiO2-x nanoplate-decorated Ti3C2 MXene hybrids for ultrafast and elevated stable lithium storage

Abstract

Novel 2D black TiO2-x nanoplate-decorated Ti3C2 MXene (TiO2-x/Ti3C2) hybrids were rationally designed and prepared by a facile wet process. The MXene nanosheets, serving as the carriers, not only enable the rapid electron and ion transport at the interface, but also avoid the aggregation of TiO2-x nanoplate during lithiation and de-lithiation. On the other hand, the presence of TiO2-x nanoplate also acts as the spacer to avert the MXene nanosheets from severe restacking. The successful formation of TiO2-x/Ti3C2 were examined by X-ray diffraction (XRD) analysis, fourier transform infrared spectroscopy (FT-IR), scanning electron spectroscopy (SEM), transmission electron spectroscopy (TEM) and X-ray photoelectron spectroscopy (XPS). When served as anodes in lithium ion batteries (LIBs), the resulting TiO2-x/Ti3C2 hybrid electrode delivers high specific capacity of 131 mA h g−1 even cycling at a high current density of 5 A g−1 (17 C) for 500 times and superior rate capability (even at a current density of 34 C, the specific capacity still remains at 115 mA h g−1), which highlight its great promise in the fields of energy storage and conversion.