Ab initio investigation of the possibility of formation of endohedral complexes between H2 molecules and B-, N- and Si-doped C60 fullerenes

Ab initio density functional theory (DFT) calculations were used to investigate the formation of endohedral complexes between H2 molecules and X-doped C60 fullerenes (X=B, N and Si). It has been found that up to two hydrogen molecules being encapsulated inside the cage can form the stable complex with all of the considered X-doped fullerenes as well as with C60 cage. The calculation results show also that 2H2@C59Si system is the most stable complex indicating potential capacity of Si-doped fullerenes for hydrogen storage.We have also investigated the possibility of formation of 3H2@C60 and 3H2@C59Si complexes and the obtained results reveal that the 3H2@C60 complex has almost zero formation energy which is metastable, while the 3H2@C59Si complex with the negative formation energy can form a stable complex thus, larger Si-doped fullerenes could be a promising material for energy storage.