Luminescence properties of Ca2Si5N8:Eu2+ prepared by gas-pressed sintering using BaF2 as flux and cation substitution

Abstract

Eu²⁺ doped Ca₂Si₅N₈ phosphors were successfully prepared by gas-pressed sintering. The red-shift of the emission band from 608 nm to the longer wavelength 622 nm of the Ca₂Si₅N₈:Eu²⁺ phosphor under blue excitation has been achieved, and a large enhancement in the emission intensity has been obtained by using BaF₂. XRD data revealed that the lattice of Ca₂Si₅N₈:Eu²⁺ was expanded with Ba²⁺ ion doping. XPS results suggested that there were more Eu²⁺ ions incorporated into the lattice of Ba²⁺ doped samples than those of the undoped samples. The doping effect of Ba²⁺ ions has been discussed in detail.