▎ 摘　　要

The present paper reports the effect of Graphene Nanoribbons (GNRs) for improving the dehydrogenation of MXH4, where M = Na, Li and X = Al, B through density functional calculations. The rectangular Armchair GNRs and ZigZag GNRs with width up to 7.57 angstrom & 10 angstrom and length of 15 angstrom &10 angstrom respectively were considered for the investigation. The effect of dopant and defect was introduced by doping with different dopants (B, N, Al, Cl and F) and introducing vacancy defect respectively. The MXH4 interacts with the surface atoms of GNRs with binding energy from 0.31-0.89 eV with AGNR and from 0.26 eV to -1.42 eV with ZGNR respectively. Charge transfer of 0.12-0.26 e take place from GNR surface to MXH4 molecule resulting in significant decrease in hydrogen release energy (E-HRE). Doped and defective AGNR lowers E-HRE of MXH4 sharply by 19-56% whereas ZGNR decreases E-HRE by 18-70% respectively. The results agree qualitatively with the available experimental result and outline the importance of nano carbon as a catalyst for improving the performance of light complex metal hydride systems. (C) 2018 Elsevier B.V. All rights reserved.