Sulfur-functionalized three-dimensional graphene monoliths as high-performance anodes for ultrafast sodium-ion storage

Sulfur-functionalized graphene monoliths with a high sulfur fraction (16.8 wt%) were prepared to demonstrate a high capacity (∼400 mA h g −1 at 0.1 A g −1 ) and ultrafast (∼120 mA h g −1 at 5 A g −1 ) sodium ion storage. The reversible reaction of -C-S x -C- with sodium ions contributes to the extra capacity while a 3D graphene network guarantees high rate capability. Sulfur-functionalized graphene monoliths with a three-dimensional porous framework as anodes show a high capacity and ultrafast sodium ion storage performance.