Wet chemical synthesis of Cu/TiO2 nanocomposites with integrated nano-current-collectors as high-rate anode materials in lithium-ion batteries

Using a soft-template assisted method, well-organized Cu/TiO2 nanoarchitectured electrode materials with copper nanowires as their own current collectors are synthesized by controlled hydrolysis of tetrabutyl titanate in the presence of Cu-based nanowires, and investigated by SEM, TEM, XRD, Raman spectroscopy and electrochemical tests towards lithium storage. Two types of Cu/TiO2 nanocomposites with different TiO2 grain sizes are obtained by using different thermal treatments. The two types of Cu/TiO2 nanocomposites show much enhanced rate performances compared with bare TiO2. A high-rate capability (reversible capacity at 7500 mA g(-1) still accounts for 58% of its initial capacity at 50 mA g(-1)) is observed for the Cu/TiO2 nanocomposite with smaller TiO2 grain size. The improvements can be attributed to the integrated Cu nanowires as mechanical supports and efficient current collectors. A cell made from the Cu/TiO2 nanoarchitectured electrodes exhibits promise as an energy storage device with both high energy and high power densities.