Energy transfer and thermal stability of K2Ba(WO4)2: Eu3+, Sm3+ phosphors

Novel red-emitting K2Ba(WO4)2: Eu3+, Sm3+ phosphors were synthesized by the solid-state reaction method. The phase formation, morphology, luminescent properties, energy transfer, concentration quenching and thermal quenching behavior were investigated. The PL intensities of the phosphors were enhanced by the addition of Sm3+ due to the energy transfer from Sm3+ to Eu3+. The analyses of PL decay curves confirmed the energy transfer from Sm3+ to Eu3+. The mechanism of energy transfer was proved to be the dipole–dipole interaction. The thermal quenching temperature of KBW: Eu3+, Sm3+ was above 463 K, indicating this phosphor had a good thermal stability. The results indicated that KBW: Eu3+, Sm3+ phosphor is a candidate of the red phosphor for w-LEDs.