An ab initio computational study of pure Zn3N2 and its native point defects and dopants Cu, Ag and Au

This paper presents the first principles, density functional theory, computations of pure zinc nitride (Zn3N2) and its doped counterparts with dopants of native elements (Zn, N) and copper family elements (Cu, Ag, Au). Atomic geometry, formation energy, and electronic structure of defects in Zn3N2 are also investigated. The formation energies of both native defects and copper family element impurities are predominantly affected by the chemical potential of different chemical species. The earlier experimental observation of electronic properties associated with nitrogen deficiency in Zn3N2 is consistent with the results of formation energy calculations. Point defects of copper family elements have an energetic preference to occupy a substitutional N site, rather than Zn or interstitial position at a special value of chemical potential of nitrogen. The calculation of defect density of states suggests that among all three copper family elements, copper is the most suitable candidate as a p-type dopant in Zn3N2.