An ionic self-assembly approach towards sandwich-like graphene/SnO2/graphene nanosheets for enhanced lithium storage

Two-dimensional graphene/SnO2/graphene (G/SnO2/G) hybrids with SnO2 nanoparticles sandwiched in graphene sheets have been constructed by a facile ionic self-assembly process. The resulting G/SnO2/G hybrids possessed flexible and ultrathin graphene shells that effectively enwrapped the SnO2 nanoparticles. When the hybrids were used as the anode materials in lithium-ion batteries (LIBs), their unique core-shell architecture provided double protection against the aggregation and volume changes of SnO2 nanoparticles, and ensured favorable transport kinetics for charge carriers. As a result, the hybrids exhibited a superior cycling stability (600 mA h g(-1) over 60 cycles) and excellent rate capability (120 mA h g(-1) at 5.0 A g(-1)).