Gas–solid interactions in the hydrogen/single-walled carbon nanotube system

Comment on “Theoretical evaluation of hydrogen storage capacity in pure carbon nanostructures” [J. Chem. Phys. 119, 2376 (2003)]

“…A recent temperature programmed desorption experiment by Shiraishi et al starting with 0.3 wt. % H 2 loading in SWNT at ambient temperature has demonstrated a H 2 adsorption energy of 4.82 kcal/mol, 10 within the range of adsorption energies we have reported. 4 The adsorption is reported to occur exclusively at the interstitial sites, which is also consistent with what we have predicted.…”

Thermodynamic properties of Pt nanoparticles: Size, shape, support, and adsorbate effects

“…E DFT denotes the DFT total energy (static energy at 0 K), F vib denotes the vibrational Helmholtz free energy, N is the number of Pt atoms constituting the NP (N=22), M is the number of H atoms on the NP, μH 2 is the vibrational and kinetic part of the H 2 chemical potential taken from experiments, 57 T is the temperature, and P is the H 2 pressure, which is considered to be 1 atm. The preference of H adsorption on edge atoms of Pt 22 was tested through the Gibbs free energy for Pt 22 H 22 by considering that (i) all H atoms adsorb at the edges and (ii) some atoms may be at facets.…”

Studies on structural defects in carbon nanotubes

“…This is because carbon nanotubes are desired to be hydrogen storage cells. The studies reveal that hydrogen molecules favorably physisorb at the exterior surface of a CNT or in the interstitial region between carbon nanotubes at room temperature and under hydrogen pressure of about 1 atm [50][51][52][53][54][55]. In contrast, when the air pressure around the carbon nanotubes increases, the H-H bond of a hydrogen molecule is broken, and the dissociated hydrogen atoms chemisorb on the outer wall of a CNT [45].…”