Vacancy Defects in Delafossite CuAlO2: First-Principles Calculations

Electronic properties and formation energies of vacancy defects in delafossite CuAlO2 have been investigated by using the first-principles density functional theory. The band structures and density of states of various vacancy defects have been obtained and analyzed. The results show that the V (Cu) systems with different charge states influence the type of conductivity. The introduced vacancy defects enhance the hybridization between O-2p and Cu-3d states, which is good for p-type conductivity. The calculated formation energies indicate that the Cu vacancy is relatively easy to form and it trends to have positive charge.