Photoluminescence of BaGdB_9O_(16):Eu^(3+) co-doped Al^(3+) or Sc^(3+) under UV-VUV excitation

摘要

Single phase of BaGd0.9-xMxEu0.1B9O16(M=Al or Sc, 0≤x≤0.3) powder was prepared by the solid-state reaction and its photoluminescence(PL) properties were investigated under ultraviolet(UV) and vacuum ultraviolet(VUV) excitation.Monitored with 613 nm emission, the excitation spectra of BaGd0.9-xMxEu0.1B9O16 consisted of three broad bands peaking at about 242, 208, and 142 nm, respectively.The one at about 242 nm originated from the charge transfer band(CTB) of O2-→Eu3+.The other two were assigned to the absorption of the host, which was overlapped with absorptions among borate groups, f→d transition of RE3+(RE=Gd, Eu), and the charge transfer transition of O2-→Gd3+.The maximum emission peak was observed at about 613 nm in the emission spectra of BaGd0.9-xMxEu0.1B9O16 under both 254 and 147 nm excitation, which originated from the electric dipole 5D0→7F2 transition of Eu3+.When excited with 254 nm, the integral emission intensity of Eu3+ increased after Al3+ or Sc3+ substituting Gd3+ partly in BaGd0.9Eu0.1B9O16.Under 147 nm excitation, the integral emission intensity of Eu3+ decreased after some Gd3+ was replaced by Sc3+, but increased after adding appropriate Al3+ into BaGd0.9Eu0.1B9O16.