Tb3+ → Sm3+ energy transfer induced tunable luminescence in Ba3MgSi2O8:Tb3+/Sm3+ phosphors

Sm3+, Tb3+ and Sm3+/Tb3+ doped Ba3MgSi2O8 phosphors were prepared by molten salts synthesis technique using NaCl/KCl mixture as the flux. The phase and optical characteristics of the prepared phosphors were researched. The XRD results revealed that the prepared phosphors have the pure Ba3MgSi2O8 phase. For Sm3+ or Tb3+ singly doped Ba3MgSi2O8 phosphors, they show characteristic emission bands of Sm3+ (exciting at 405 nm) or Tb3+ (exciting at 233 nm) ions. Exciting at 233 nm, Sm3+/Tb3+ codoped Ba3MgSi2O8 phosphors show emission band corresponding to Sm3+ and Tb3+ ions. Tb3+ → Sm3+ energy transfers occur in Sm3+/Tb3+ codoped Ba3MgSi2O8 phosphors, which leads to the tunable luminescence of them. The CIE coordinates change from (0.431, 0.515) for Ba3MgSi2O8:0.12 Tb3+/0.01Sm3+ to (0.555, 0.425) for Ba3MgSi2O8:0.12 Tb3+/0.05Sm3+. The color of light changes from green-yellow for Ba3MgSi2O8:0.12 Tb3+/0.01Sm3+ to red-yellow for Ba3MgSi2O8:0.12 Tb3+/0.05Sm3+.