Investigation of Europium dopant in the orthophosphate KMPO4 (M = Ba and Sr) compounds

Abstract

Abstract Atomistic simulations based on lattice energy minimization are used to investigate trivalent and divalent Europium dopant ions in the structure of KMPO4 (M\u202f=\u202fBa and Sr). Interatomic potentials are developed, and the structural properties calculated in this way show good agreement with experimental values. These calculations suggest that Eu3+ and Eu2+ ions are the most energetically provable to be incorporated at divalent (M\u202f=\u202fBa and Sr) host sites. It is also predicted that the Eu divalent dopant is charge-compensated by KMʼ anti-site defects. Four reduction-doping process schemes (open atmosphere, CO, N2 and H2 reducing atmosphere) are investigated here, and it is observed that a CO reducing atmosphere is the most effective agent for Eu reduction. The results showed that the preferred host site, charge compensation and schemes for the reduction-doping process for Eu doping ions play important roles in an understanding of the luminescent properties of KMPO4 (M\u202f=\u202fBa and Sr) phosphates.