Tunable emission, energy transfer, and charge compensation in the CaSb2O6:Eu3+, Bi3+ phosphor

Novel CaSb 2 O 6 :Eu 3+ , Bi 3+ phosphor is synthesized by solid-state reaction method in air. Their crystal structures are investigated. Luminescence properties of CaSb 2 O 6 :Eu 3+ , CaSb 2 O 6 :Bi 3+ , and CaSb 2 O 6 :Eu 3+ , Bi 3+ phosphors are compared, analyzed and explained, respectively. Tunable emission of CaSb 2 O 6 :Eu 3+ , Bi 3+ phosphor with excitation 298 nm can be observed by changing Eu 3+ or Bi 3+ concentration. Energy transfer (ET) and charge compensation in CaSb 2 O 6 :Eu 3+ , Bi 3+ phosphor are observed and analyzed via its luminescence properties. Lifetimes of CaSb 2 O 6 :5 %Eu 3+ , yBi 3+ phosphor (0.5 ≤ y ≤ 5 mol%) are investigated, which further confirm that ET process can be formed between Eu 3+ ion and Bi 3+ ion. The luminous mechanism is explained via the energy level diagrams of Bi 3+ and Eu 3+ ions. The emission properties indicate that CaSb 2 O 6 :Eu 3+ , Bi 3+ phosphor has a potential application for white LEDs based on near UV (~394 nm) LED chip.