Atomic and Electronic Structure Investigation and Luminescence Property of Eu2+-Doped beta-SiAlON Green Phosphor: Ab initio Calculations

Abstract

The atomic and electronic structure of Eu-doped beta-SiAlON with various Al-O pair concentrations was calculated using density functional theory. The luminescence properties were analyzed by using quantitative calculation of the bandgap and the wavelength. Interstitially doped Eu ion was found near N atoms in the atomic channel parallel to the [0001] axis and the lattice parameters of the primitive cell became larger as the Al-O pair concentration increased. The additional states originated from the hybridization of Eu 4f with Si 3p and N 2p. The calculated wavelengths from the energy gap between the valance band maximum and the extra level was about 540nm in the high Al-O pair concentration. The calculated results are well agreed with experimental results.