La2MgTiO6:Bi3+/Mn4+ photoluminescence materials: Molten salt preparation, Bi3+ → Mn4+ energy transfer and thermostability

Bi3+, Mn4+ and Bi3+/Mn4+ doped La2MgTiO6 photoluminescence materials were prepared by molten salt process using the mixture of NaCl/KCl as the fluxing agent. All of prepared photoluminescence materials have the similar crystal structure with La2MgTiO6 host, indicating that the dopants have entirely doped into the host and formed solid solution. Bi3+ or Mn4+ singly doped La2MgTiO6 photoluminescence materials respectively exhibit characteristic photoluminescence bands of Bi3+ and Mn4+ while they are excited. For Bi3+/Mn4+ codoped La2MgTiO6 photoluminescence materials, photoluminescence bands of Bi3+ and Mn3+ are observed and there is the occurrence of Bi3+ → Mn4+ energy transfer. The Bi3+ → Mn4+ energy transfer is confirmed by the decreasing photoluminescence intensity and lifetime of Bi3+ with the increasing Mn4+ concentration. The thermostabilities of the prepared photoluminescent materials were also researched to show their applications in various fields.