Near UV-pumped yellow-emitting Ca3TeO6:Dy3+ phosphor for white light-emitting diodes

Abstract A series of Ca 3 TeO 6 : x Dy 3+ ( x  = 0.01, 0.02, 0.05, 0.10, 0.15, 0.20, and 0.25) tellurate yellow-emitting phosphors were synthesized via the high-temperature solid-state method. The X-ray diffraction patterns of these phosphors revealed that all the samples have a double-perovskite type with monoclinic structure. The Ca 3 TeO 6 :Dy 3+ phosphor exhibit characteristic emission transitions, 4 F 9/2 – 6 H 15/2 transition and 4 F 9/2 – 6 H 13/2 transition, respectively. The intense yellow light indicates that Dy 3+ ion occupies the interstitial Ca site in the Ca 3 TeO 6 host. The optimal Dy 3+ ion concentration was determined as 10 mol%. The critical energy transfer distance was calculated as 14 A. The concentration quenching mechanism of Dy 3+ was investigated in details. The temperature effect on photoluminescence was discussed in order to evaluate the thermal stability. The obtained results illustrate Ca 3 TeO 6 :Dy 3+ was a new kind of yellow-emitting potential phosphor for WLEDs.