Fast and reversible hydrogen storage in channel cages of hydroquinone clathrate

Guest-free hydroquinone (HQ) clathrate was synthesized by the gas-phase reaction between host HQ and guest CO2 molecules, followed by removal of the CO2 guests by controlled heating process. The H2 storage capacity of the guest-free HQ clathrate is highly sensitive to the loading pressure; at 298K, it was found to be 0.19 wt.% at 10MPa and 0.38 wt.% at 35MPa. In particular, the guest-free HQ clathrate also exhibits an extremely fast uptake and release of H2 in a time scale of a few seconds.