Alkali cations and H2 molecules on BN-doped carbon nanoflakes: Theoretical study

Non-covalent interactions of two cations (Li+ and Na+) and hydrogen molecules with coronene and hexagonal boron nitride models as well as their heterostructures (mBNC and pBNC) were studied by using a set of theoretical methods. It was shown that the shapes of boron nitride moieties in the graphene-like framework have a strong influence on the cation-π interactions. Decomposition of the interaction energy (Eint) was classified as consisting mainly of the inductive energy term (Eind), which is followed by the electrostatic term (Eel). Hydrogen adsorption, however, depends strongly on both these terms, and in the case of numerous adsorbed H2 molecules, the dispersion interactions (Edisp) are also of importance. The assessed hydrogen capacity of studied structures reaches 5.5 wt%. The present investigation explicitly shows that cation-π and, in some cases, hydrogen adsorption properties can be easily modified by a B and N atoms introduction in the carbon nanoflakes, and, hence, it establishes the route to the remarkable adsorbent materials. [Display omitted] •Four BNC heterostructures for hydrogen adsorption are modeled.•Li+ and Na+ decorations substantially improve H2 adsorption.•SAPT0 reveals that cation adsorption is mainly due to Eind interactions.•SAPT0 shows the different energy patterns for hydrogen adsorption.•Decorated mBNC system exhibits the best performance for H2 storage.