The interaction of hydrogen with corannulene, a promising new platform for energy storage

The interaction between corannulene and hydrogen, either as an atom (H) or molecule (H2), has been investigated by means of muon-spin-resonance techniques at 40 K and 410 K, as well as H2-sorption experiments at 77 K. H2 adsorption occurs via weak van-der-Waals interactions following a type-V isotherm with a gravimetric storage capacity of 0.1 wt% H2, corresponding to about one hydrogen molecule per unit cell. These results indicate that H2 diffusion can take place in bulk corannulene. Furthermore, we find that the corannulene molecule exhibits a markedly strong ability to capture H, as inferred from the formation of long-lived muonium-adduct radicals. All of these features are of relevance for the use of corannulene as a hydrogen-storage medium, in combination with, for example, alkali metals or catalysts. On the basis of our experimental results, we conclude that corannulene-based materials constitute a promising and yet-to-be-explored alternative to fullerenes in the extensively studied class of alkali-intercalated nanocarbons.