Photoluminescence enhancement in Na 3 SO 4 Cl:X (X = Ce 3+ , Eu 3+ or Dy 3+ ) material

The compound Na 3 SO 4 Cl X (X = Ce 3+ , Eu 3+ or Dy 3+ ) prepared by the wet chemical method was studied for its photoluminescence (PL) and energy transfer characteristics. The PL from Na 3 SO 4 Cl:Ce 3+ shows strong emission at 322 nm at an excitation of 272 nm. Therefore, an efficient Ce 3+  → Dy 3+ , Eu 2+  → Dy 3+ and Eu 2+  → Eu 3+ energy transfer had taken place in this host. The Dy 3+ emission caused by Ce 3+  → Dy 3+ energy transfer under ultraviolet (UV) wavelengths peaked at around 477 nm and 572 nm due to 4  F 9/2  →  6 H 15/2 and 6 H 13/2 transitions with yellow–orange emission in the Na 3 SO 4 Cl lattice. An intense Dy 3+ emission was observed at 482 and 576 nm caused by the Eu 2+  → Dy 3+ energy transfer process and due to 4  F 9/2  →  6 H 15/2 and 4  F 9/2  →  6 H 13/2 transitions respectively. The Eu 3+ blue to red light emission caused by the Eu 2+  → Eu 3+ energy transfer peaked at 593 nm and 617 nm due to 5 D 0  →  5 D 3 transitions. The presence of trivalent Eu in Na 3 SO 4 Cl suggested the presence of Eu 3+ in the host compound that occupied two different lattice sites and that peaked at 593 and 617 nm due to 5 D 0  →  7  F 1 and 5 D 0  →  7  F 2 transitions respectively. The trivalent europium ion is very useful for studying the nature of metal coordination in various systems due to its non‐degenerate emitting 5 D 0 state. The present paper discusses the photoluminescence characteristics of Eu 2+  → Dy 3+ and Eu 2+  → Eu 3+ energy transfer. This compound may be useful as a lamp phosphor. Copyright © 2015 John Wiley & Sons, Ltd.