| Abstract: | The hydrogen storage behavior of Sc-decorated WS_2 monolayer and WS_2 nanoribbons is systematically studied by using first principles calculations based on the density functional theory.The present results indicate that an Scdecorated WS_2 monolayer is not suitable for storing hydrogen due to the weak interaction between the monolayer WS_2 sheet and the Sc atoms.It is found that both the hybridization mechanism and the Coulomb attraction make the Sc atoms stably adsorb on the edges of WS_2 nanoribbons without ciustering.The 2SC/WS_2NRS system can adsorb at most eight H_2 molecules with average adsorption energy of 0.20eV/H_2.The resuits show that the desorption of H_2 is possible by lowering the pressure or by increasing the temperature. |
