Li-decorated metal-organic framework 5 : A route to achieving a suitable hydrogen storage medium

• A significant improvement in molecular hydrogen uptake properties is revealed by our ab initio calculations for Li-decorated metal-organic framework 5. We have found that two Li atoms are strongly adsorbed on the surfaces of the six-carbon rings, one on each side, carrying a charge of +0.9e per Li atom. Each Li can cluster three H-2 molecules around itself with a binding energy of 12 kJ (mol H-2)(-1). Furthermore, we show from ab initio molecular dynamics simulations with a hydrogen loading of 18 H2 per formula unit that a hydrogen uptake of 2.9 wt % at 200 K and 2.0 wt % at 300 K is achievable. To our knowledge, this is the highest hydrogen storage capacity reported for metal-organic framework 5 under such thermodynamic conditions.

Ämnesord

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Nyckelord

first-principles calculations

molecular adsorption

molecular

dynamics

porous materials

doped carbon nanotubes

design

molecules

crystals

binding

surface

energy

sites

Physics

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)