Stereotaxically Constructed Graphene Modification of CuO-Cu 2 O/TiO 2 Microspheres for Boosted Lithium and Sodium Storage Performance

A facile hydrothermal approach has been developed to synthesize a CuO-Cu 2 O/TiO 2 /stereotaxically constructed graphene (SCG) composite, which involves two main steps: the creation of anatase TiO 2 microspheres and the formation of the CuO-Cu 2 O/TiO 2 /SCG composite by a subsequent one-step hydrothermal treatment, in which CuO-Cu 2 O and TiO 2 particles adhere to SCG. The design of combining CuO-Cu 2 O with the TiO 2 and SCG layers is favorable to enhancing electronic conductivity and buffering the severe volume change. When assembled as anode materials for Li-ion batteries (LIBs) and Na-ion batteries (SIBs), the CuO-Cu 2 O/TiO 2 /SCG composite exhibits excellent capacity of 797.4 mA h g −1 at 0.1 A g −1 after 100 cycles for LIBs and 354.7 mA h g −1 at 0.1 A g −1 after 50 cycles for SIBs. An exceptional rate capability is also obtained: 782.8 and 578.1 mA h g −1 at 0.3 and 2 A g −1 for LIBs, respectively; 390.6 and 329.9 mA h g −1 at 0.3 and 0.5 A g −1 for SIBs, respectively. Graphic Abstract