Energy transfer between Ce 3+ → Gd 3+ or Tb 3+ in KNaSO 4 microphosphor

KNaSO 4 microphosphor doped with Ce,Gd and Ce,Tb and prepared by a wet chemical method was studied using X‐ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL) characterization. KNaSO 4 has a 5‐µm particle size detected by SEM. KNaSO 4 :Ce 3+ ,Tb 3+ showed blue and green emission (at 494 nm, 557 nm, 590 nm) of Tb 3+ due to 5 D 4  →  7 F J (J = 4, 5, 6) transitions. KNaSO 4 :Ce 3+ ,Gd 3+ showed luminescence in the ultraviolet (UV) light region at 314 nm for an excitation at 271 nm wavelength. It was observed that efficient energy transfer took place from Ce 3+  → Gd 3+ and Ce 3+  → Tb 3+ sublattices indicating that Ce 3+ could effectively sensitize Gd 3+ or Tb 3+ (green emission). Ce 3+ emission weakened and Gd 3+ or Tb 3+ enhanced the emission significantly in KNaSO 4 . This paper discusses the development and understanding of photoluminescence and the effect of Tb 3+ and Gd 3+ on KNaSO 4 :Ce 3+ . Copyright © 2015 John Wiley & Sons, Ltd.