Theoretical investigation of an acid catalyst for viable release of H2 from BN nanotubes: A local pair natural orbital coupled cluster approach

Catalytic removal of H₂ from boron-nitride (BN)-based nanomaterials at ambient conditions is of paramount importance in order to develop lightweight hydrogen storage media. Here, the DLPNO-CCSD(T) technique is used to calculate accurate relative energies and activation barriers of Brønsted acid-initiated removal of H₂ from hydrogenated BN nanotubes (HBNNTs) with six different acids. Three crucial steps are identified in the mechanism: first H₂ release, catalyst regeneration via proton transfer, and second H₂ release to ensure feasibility of the dehydrogenation proposal. Our computational studies reveal that sulfonic acids with appropriate electrophilicity can facilitate dehydrogenation of HBNNT at a low free energetic cost (∆G^‡ = 17 kcal/mol). Importantly, these findings illustrate the possibility of H₂ release from BN nanomaterials at ambient conditions and provides hope for a sustainable chemical hydrogen storage strategy.