Ca₂BO₃Cl:Ce³⁺, Tb³⁺: A novel tunable emitting phosphor for white light-emitting diode

Ca₂BO₃Cl:Ce³⁺, Ca₂BO₃Cl:Tb³⁺, and Ca₂BO₃Cl:Ce³⁺, Tb³⁺ phosphors are synthesized by a high temperature solid-state reaction. The emission intensity of Ce³⁺ or Tb³⁺ in Ca₂BO₃Cl is influenced by the Ce³⁺ or Tb³⁺ doping content, and the optimum concentrations of Ce³⁺ and Tb³⁺ are 0.03 mol and 0.05 mol, respectively. The concentration quenching effect of Ce³⁺ or Tb³⁺ in Ca₂BO₃Cl occurs, and the concentration quenching mechanism is d-d interaction for either Ce³⁺ or Tb³⁺. The Ca₂BO₃Cl:Ce³⁺, Tb³⁺ can produce colour emission from blue to green by properly tuning the relative ratio between Ce³⁺ and Tb³⁺, and the emission intensity of Tb³⁺ in Ca₂BO₃Cl can be enhanced by the energy transfer from Ce³⁺ to Tb³⁺. The results indicate that Ca₂BO₃Cl:Ce³⁺, Tb³⁺ may be a promising double emission phosphor for UV-based white light emitting diode.