Ab initio investigation of the influence of single intrinsic defect on the structure, bulk moduli and electronic properties of Ⅴ-doped ZnO

摘要

We researched the effect of single intrinsic defect of the structure and electronic properties of Ⅴ-doped ZnO.After vanadium (Ⅴ) atom replaced one zinc atom,lattice constants and bulk modulus increased slightly 1.2％ and as high as 8.9％,respectively.The total energy showed that oxygen defect inclined to stay at a position far from Ⅴ atom but zinc defect likely to localize at a position near Ⅴ atom.The electronic density state of pure ZnO was semiconductor behavior.Vanadium doping introduced a spin-polarization around Fermi-level.The 3d orbital of Ⅴ split into triplet-state ta (antibonding state),dual-state e (nonbonding state) and triplet-state tb (bonding state) in the wurtzite ZnO crystal field.The ta state hybridized with O2p state above Fermi-level,which made Znl5VOl6 underwent a semiconductor-halfmetal transition.Vanadium substitution moved the electronic density states to lower energy.Oxygen defect had little effects on Ⅴ-doped ZnO while zinc defect moved the density of states to higher energy.Our paper provided a reference for the preparation and application of Ⅴ-doped ZnO.