Intrinsic half-metallicity in hydrogenated boron-nitride nanoribbons

We have investigated the structural and electronic characteristics of fully hydrogenated boron-nitride (BN) layer and zigzag-edged nanoribbons using dispersion-corrected density-functional calculations. In the fully hydrogenated BN structure, the hydrogen atoms adsorb on top of the B and N sites, alternating on both sides of the hexagonal BN-plane in a specific periodic manner. Among various low-energy hydrogenated membranes referred to as chair, boat, twist-boat, and stirrup, the stirrup conformation is the most energetically favorable one. The zigzag-edged BN nanoribbon, prominently fabricated in experiments, possesses intrinsic half-metallicity with full hydrogenation. The half-metallicity can be tuned by applying a transverse electric bias, thereby providing a promising route for spintronics device applications.