Graphene towers promise ‘flexi-electronics’

The 3D ‘monoliths’ --- grown between forming ice crystals --- add elasticity to the super-strength and conductivity of graphene sheets
December 10, 2012

The graphene towers’ honeycomb structure gives it super-strength and resilience (credit: L. Qiu, Monash University)

It can support 50,000 times its own weight, springs back into shape after being compressed by up to 80%, and has a density much lower than most comparable metal-based materials.

It’s a new superelastic, 3D form of graphene developed at Monash University that can even conduct electricity, paving the way for flexible electronics, Nature News reports.

The researchers adapted an industrial technique called freeze casting to do just that. This involves growing layers of an oxygen-coated, soluble version of graphene called graphene oxide between forming ice crystals. On cooling the aqueous solution of graphene oxide flakes, a thin layer of the nanomaterial becomes trapped between the growing crystals, forming a continuous network that retains its structure once the ice is thawed.

The new graphene’s properties are attributed to its structure: the individual graphene sheets are neatly aligned, forming an ordered network of hexagonal pores.

The structure could be used as a scaffold for flexible battery electrodes, or form the basis of many composite materials, or for biomedical applications, because the pore sizes match existing tissue scaffolds very well.