Reversible Hydrogen Storage by Controlled Buckling of Graphene Layers

We propose a multilayer graphene-based device in which the storage and release of hydrogen are obtained by exploiting and controlling the corrugation of individual layers of graphene. By means of calculations based on the density-functional theory, we quantify the tunability of the hydrogen-graphene binding energies by changing the sheet out-of-plane deformation up to ±0.2 Å. We show that the binding energy can be varied by more than 2 eV, with the convex regions allocating the energetically favored hydrogen binding sites. We simulate the process of hydrogen chemisorption on corrugated graphene and release under the application of time-dependent mechanical deformations. Our results show that the corrugation of the graphene sheet and the controlled inversion of its curvature yield fast storage and release of hydrogen. Our corrugated graphene multilayer system can potentially reach gravimetric capacities up to 8 wt % and reversibly store and release hydrogen by external control of the local curvature at room conditions and with fast kinetics.