Tunable electronic structures and magnetic properties in two-dimensional stanene with hydrogenation

Based on tight-binding model and first-principles calculations, we systematically investigate the geometric, electronic, and magnetic properties of hydrogenated stanene. The results indicate that the half hydrogenation breaks the pi-bondings of stanene, leaving pi electrons in unsaturated Sn atoms localized and unpaired, which makes it transform into half-metal (HM) with room-temperature ferromagnetism. Especially, the magnetism of hydrogenated stanene can be effectively tuned by different rates of coverage for hydrogen atoms. While for the case of full-hydrogenated stanene, two different configurations exhibit the nature of semiconductor and semimetal, respectively, which is dependent on the arrangement of hydrogen atoms. We also find that the band gaps of stanane bilayer and monolayer can be effectively modulated by external electric field and strain. These findings demonstrate that hydrogenation is an efficient way to tune the electronic properties of stanene, and it provides a new perspective for the potential application in nanoelectronics. (C) 2016 Elsevier B.V. All rights reserved.