Evolution of the electronic and magnetic properties of zigzag silicene nanoribbon used for hydrogen storage material

Using first-principles calculations, we investigate the evolution of electronic and magnetic properties of zigzag silicene nanoribbon (ZSiNR) along with the concentration of edge adsorbed hydrogen adatoms. Our study shows that the significant covalent bonding helps to stabilize the configurations of hydrogen adsorbed ZSiNRs. The ferro-metallic electronic property of ZSiNR originated from the s-p mixing effect is suppressed by mono-hydrogenation at the adsorption sites due to the sp(2) bonding. However, bi-hydrogenation at the adsorbed sites will lead to the typical sp(3) bonding, which dominates the electronic property with the increasing of hydrogen adatoms. Under the coexisting situation with mono-hydrogenation and bi-hydrogenation, we find that both the number of adsorption sites and the bonding type of sp(2) or sp(3) have impact on the electronic property of ZSiNR. It is found that symmetry adsorption at the edges changes the stable magnetic state of ZSiNR from ferromagnetic to antiferromagnetic. In contrast, unsymmetrical adsorption along the two edges of ZSiNR keeps its ferromagnetic property. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.