Hydrogen adsorption on graphene: a first principles study

Cooperative Interplay of van der Waals Forces and Quantum Nuclear Effects on Adsorption: H at Graphene and at Coronene

“…As expected, and in agreement with many previous DFT GGA studies, the barrier between the gas phase and the chemisorbed state is about 200 meV. 16,19,[32][33][34][35] The chemisorption well is 800 meV with a H−C bond length of 1.13 Å and puckering of the top site carbon atom away from the surface by ∼ 0.4 Å. With PBE there is no physisorption state, which is again consistent with previous work and understandable given the lack of a long-range correlation term in GGA exchange-correlation functionals.…”

“…This barrier -which includes vdW, ZPE effects, quantum tunneling and finite temperature effects -is approximately half the height of barriers typically predicted for H atom chemisorption at graphene using traditional DFT-GGA methods. 16,19,[32][33][34][35] Although the barrier is substantially reduced the physisorption well remains relatively unperturbed, being a similar depth and shifted towards the gas phase by just ∼ 0.1 Å.…”

“…Hydrogen adsorption on carbon based materials such as graphite and graphene is relevant to hydrogen storage, 9 band gap engineering, [10][11][12][13] and potentially as the first step in H 2 formation in the interstellar medium. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] Although there is enormous interest in H adsorption on carbonaceous surfaces, with graphene, graphite and polycyclic aromatic hydrocarbons (PAHs) being the most widely studied model systems, we still don't fully understand the seemingly simple process of how a single H atom adsorbs on the surface.…”

Hypothetical planar and nanotubular crystalline structures with five interatomic bonds of Kepler nets type

“…Such method led to the binding energy for graphene equal -7.83 eV that is attractive fit to the results received by other authors. [31][32][33] The fit supports our approach.…”

Hydrogen transport on graphene: Competition of mobility and desorption

“…9 Similarly, hydrogen storage on graphene, in spite of excellent gravimetric characteristics, will be seriously considered only provided one solves the well-known dilemma encountered in other carbon nanostructures (nanotubes and fullerenes)-that is, reconciling the high storage efficiency (sufficiently strong carbon-hydrogen binding) at room temperature with the reasonable ease of reversible hydrogen charging/discharging. Indeed, the most recent evaluations 21,22 give the potential barrier of ∼1.1 eV for chemisorbed hydrogen dissociation from graphene. With this desorption energy, it is easy to verify that the average lifetime of individual hydrogen atom on graphene at room temperature is less than a week.…”