Remarkable improvement in hydrogen storage capabilities of graphitic carbon nitride nanosheets under selected transition metal embedding: A DFT study

The adsorption performance of hydrogen molecules over the transition metals (TM = Os, Ru, and Fe)-embedded graphitic carbon nitride (gCN) and also the binding energy of these TM elements over the gCN are investigated using DFT computations. The obtained results showthat the interaction energy between Os-embedded gCN and H-2 molecule (with Eads of -2.452 eV) is superior than those of the other reported adsorbents. Based on these results, it is inferred that the maximum storage number of H-2 molecules adsorbed over the TM -embedded gCN are 6 hydrogen molecules. The results reveal that with adsorption of H-2 molecules over the gCN, conduction band and valence band energy levels have crossed each other close to the Fermi level EF, thus the semi-conductive behavior of these systems is converted to a conductive state. Finally, it is concluded that the Os-modified gCN is suitable for storaging of H-2 molecules. (c) 2021 Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.

Automated summary

DFT computations were used to investigate the adsorption performance of hydrogen molecules over transition metals embedded graphitic carbon nitride, showing that Os-embedded gCN has superior interaction with H-2 molecules. The maximum storage number of adsorbed H-2 molecules was found to be 6. Adsorption of H-2 molecules converted the semi-conductive behavior of the systems to a conductive state.