Half-Metallic Properties Induced by Fluorine in Aluminum Nitride Nanosheet

Abstract

We performed first-principles simulations to study the geometric, electronic and magnetic properties as well as the binding energies of the two-dimensional AlN nanosheets with or without fluorination. The results show that the pristine multi-layer AlN sheets prefer the planar graphite structures due to the weak ionic bonding between two layers. Half-fluorination only on Al sites lead to the flat structure transform to the buckled one, resulting in a semiconductor–ferromagnetic metal transition with magnetic moments of 1.0, 1.0, 0.97, and 0.83 µ B per unit cell for one, two, three, and four-layer sheets, respectively. Especially, the fluorinated single- and two-layer AlN sheets exhibit an intriguing half-metallic behavior, while the thicker multi-layer sheets show metallic properties. These results indicate that fluorination on Al sites might be an efficient route to tune their electronic and magnetic properties to realize potential applications in nanoelectronics and spintronics.