Thickness-dependent surface energies of few-layered arsenene and antimonene films in α and β phases

Highlights: • The surface properties of layered As (Sb) are studied by using DFT. • The surface energies of β-As (Sb) exhibit thickness-dependent properties. • The interlayer distance plays an important role on surface energy. Group V elemental few-layered materials with semiconducting electronic properties are emerging as promising 2D layered materials. Since the layered configurations need substrate for device fabrications, their surface energy values could decide their properties. Here, we have performed a systematic density functional theory (DFT) investigation on the surface energies of arsenene and antimonene films as the function of thickness. The results show that the surface energy of β phase increases with increased layered numbers and converges to a constant value at about five layers, while the surface energy of α phase is size-independent. Since the surface energies of both α and β phase are similar, there is the existence possibility of α phase. Those could give references for future manufacture of arsenene and antimonene nano-devices.