Ca3La6Si6O24:Eu3+ orange-red-emitting phosphor: Synthesis, structure and luminescence properties

Ca 3 La 6 Si 6 O 24 :Eu 3+ phosphors are synthesized in air through high-temperature solid-state reaction method. The crystal structure, morphology, and luminescence properties are investigated. Ca 3 La 6 Si 6 O 24 :Eu 3+ phosphor emits orange-red light in the range of 570–750 nm due to the 5 D 0 → 7 F S ( S  = 0, 1, 2, 3, and 4) transitions of Eu 3+ ion. The optimal Eu 3+ doping concentration is ∼8 mol%. The energy transfer mechanism is the electric multipolar interactions. The luminescence lifetimes are ∼1.70, 1.66, 1.62, 1.57, 1.51, and 1.49 ms for x  = 2, 4, 6, 8, 10, and 12 mol%, respectively. Ca 3 La 6 Si 6 O 24 :Eu 3+ phosphor shows excellent thermal stability with the E a value ∼0.3314 eV. The luminous and temperature quenching mechanisms are explained by the energy level diagram and configurational coordinate diagram of Eu 3+ ions, respectively. The experimental results indicate that Ca 3 La 6 Si 6 O 24 :Eu 3+ phosphor has a potential application in white light-emitting diodes (LEDs) based on the near UV (394 nm) LED chip.