Fig. 1.

Sulfur template control of incorporated void space. a Schematic of the limited space produced after the shrinkage of a 3D graphene assembly, leading to cracking of the graphene cage and electrode pulverization when the SnO₂ expands during the lithium storage process. b When an appropriate amount of sulfur is used as a sacrificial template for incorporating void space, the SnO₂ has enough space for lithiation. Note that sulfur removal could result in the production of the smallest sufficient void space, thus achieving high volumetric performance. c The removal of excess sulfur would introduce a large void space and compromise the volumetric capacity