Influence of different terminals on the surface properties of rare earth tetraborides: First-principle calculations

Abstract

Rare-earth tetraborides (RB4) have attracted much attention as a kind of promising optoelectronic materials. Understanding their surface stability and morphology is the first and essential step in exploring their properties. We systematically reported the surface and optical properties of five RB4 (R = La, Ce, Gd, Tb and Dy) by first-principles calculations. The results are in good agreement with the available experimental measurements, which indicate that tetraborides are potential electron emission and radiation shielding materials. Interestingly, the surfaces of the metal terminations of RB4 had low work functions and surface energies. In addition, the optical properties calculations show that tetraborides have excellent optical absorption in the ultraviolet–visible region.