Graphene-Encapsulated Copper tin Sulfide Submicron Spheres as High-Capacity Binder-Free Anode for Lithium-Ion Batteries

based sulfides are potential anode materials for lithium-ion batteries (LIBs); nevertheless, they typically suffer from poor cycle stability resulted from the huge volume variation during lithium-ion insertion and extraction. Herein, we successfully fabricated the multiphase Cu2Sn3S7/Cu2SnS3/SnS2 (CTS) submicron spheres uniformly incorporated with reduced graphene oxide nanosheets (CTS@RGO). This binder-free hybrid CTS@RGO paper exhibits favorable capacity retention as an anode of LIBs (965 mAhg(-1) after 300 cycles at current density of 500 mAg(-1)), as well as better rate capability and high initial coulombic efficiency compared with that of a pristine CTS anode. The enhanced electrochemical performance can be ascribed to the introduction of graphene as a buffer to accommodate large volume changes and to maintain structural integrity of electrode.