Hydrogen storage in high surface area graphene scaffolds

Abstract

Using an optimized KOH activation procedure we prepared highly porous graphene scaffold materials with SSA values up to 3400 m² g⁻¹ and a pore volume up to 2.2 cm³ g⁻¹, which are among the highest for carbon materials. Hydrogen uptake of activated graphene samples was evaluated in a broad temperature interval (77–296 K). After additional activation by hydrogen annealing the maximal excess H₂ uptake of 7.5 wt% was obtained at 77 K. A hydrogen storage value as high as 4 wt% was observed already at 193 K (120 bar H₂), a temperature of solid CO₂, which can be easily maintained using common industrial refrigeration methods.