Facile synthesis of ultrathin-shell graphene hollow spheres for high-performance lithium-ion batteries

• Ultrathin-shell graphene hollow spheres were synthesized by a simple template assisted method without surfactant.
• The thickness of the shell is uniform and only 5 nm.
• The graphene hollow spheres show excellent electrochemical performance.

In this work, ultrathin-shell graphene hollow spheres have been designed and synthesized from the graphene oxide nanosheets by a simple template assisted method without surfactant. It is found that the obtained graphene hollow spheres have a high surface area (248.3 m2 g−1), ultrathin porous shells (5 nm) and an interconnected structure. More strikingly, the as-prepared graphene hollow spheres exhibit outstanding electrochemical performance as an anode material for lithium-ion batteries. Even at a high current density of 5000 mA g−1, a high reversible specific capacity of 249.3 mAh g−1 can be achieved. Furthermore, after 100 cycles, about 97.1% of the specific capacity is maintained at a high current density of 1000 mA g−1. The excellent electrochemical properties could be attributed to the attractive structure advantages of the graphene hollow spheres including the high surface area, ultrathin porous shells and an interconnected structure.