Structural, electronic, and optical properties of hexagonal and triangular SiC NWs with different diameters

Silicon carbide (SiC) is a wideband gap semiconductor with great application prospects, and the SiC nanomaterials have attracted more and more attention because of their unique photoelectric properties. According to the first-principles calculations, we investigate the effects of diameter on the electronic and optical properties of triangular SiC NWs (T-NWs) and hexagonal SiC NWs (H-NWs). The results show that the structure of H-NWs is more stable than T-NWs, and the conduction band bottom of H-NWs is more and more deviated from the valence band top, while the conduction band bottom of T-NWs is closer to the valence band top. What is more, H-NWs and T-NWs have anisotropic optical properties. The result may be helpful in developing the photoelectric materials.