Exploring electronic properties, surface energies and cleavage energies of low-Index surfaces of AlB2 by first-principles calculation

Abstract

In this work, employing density functional theory (DFT) simulations and calculations, a thorough analysis of surface relaxation, electronic structure, and charge distribution on various low-index surfaces of AlB2 was performed. It reveals the existence of uniform internal structures on the Al-(0001) and B-(0001) surfaces, while revealing the non-uniform nature of the Al-(10 1‾ 0) and B-(101‾ 0) surfaces. Furthermore, the (112‾ 0) surface has a relatively unstable configuration, characterized by a notable propensity for Al atoms to migrate more freely. Besides, the stability of these surfaces under different chemical potential conditions was also explored. It is worth noting that, in the Al-rich condition, the Al-(0001) surface assumes thermodynamic favorability, whereas in the B-rich condition, the B-(0001) surface exhibits higher stability. The calculation of the work function emphasizes the unique characteristics of the B-(0001) surface, since it has the highest work function. This observation indicates that the electron release energy from this surface is relatively high, implying unique properties and promising application potential.