First-Principles Study on Optical Properties of Cd-Doped Single-Walled (8, 0) ZnO Nanotube

Abstract

The band structures, density of states, and absorption spectra of pure and Cd doped single-walled (8, 0) ZnO nanotubes are calculated using first-principles based on density functional theory. The calculation results show that the import of Cd leads a remarkable decrease to the forbidden bandwidth of ZnO. Consequently, more electrons in the valence band can be motivated to the conduction band by the visible light, which results in a further enhancement of visible light absorption and a wider absorption range.