Eu2+, Dy3+: Sr2B5O9Cl, a new blue-emitting phosphor with long persistence

A new Eu2+, Dy3+: Sr2B5O9Cl phosphor with long persistence was synthesized in a reducing atmosphere by a solid-state reaction process. The pure-phase phosphor was obtained by calcination at 900 degrees C. The introduction of Eu2+ into the lattice of the matrix resulted in a broad blue emission centered at 423 nm, which was due to the characteristic 4f6(5)d(1) to 4f(7) energy transfer of Eu2+ ions. Both Eu-doped and Dy/Eu-codoped phosphors displayed afterglow behaviors due to the electron traps generated by the incorporation of tri-valanced rare earth cations into the original Sr lattice sites. The afterglow of Eu2+: Sr2B5O9Cl and Eu2+, Dy3+: Sr2B5O9Cl phosphors showed standard double exponential decay behaviors, and the Eu2+/Dy3+ co-doped sample demonstrated better afterglow properties than Eu2+-doped one. A longer lifetime for the electrons was confirmed after the afterglow decay curve simulation. Based on the analysis of thermally stimulated luminescence (TSL), the difference in afterglow was attributed to the different trap concentrations induced by the Dy3+ (Eu3+) doping in the Sr2B5O9Cl matrix.

Automated summary

A new Eu2+, Dy3+: Sr2B5O9Cl phosphor with long afterglow was synthesized through a solid-state reaction in a reducing atmosphere. The introduction of Eu2+ resulted in blue emission, with the Dy3+/Eu3+ co-doped sample showing better afterglow properties.