Tunable blue-green emission phosphor Ca2PO4Cl:Ce3+, Tb3+: Luminescence and energy transfer

A series of tunable emission phosphors Ca2PO4Cl:Ce3+, Tb3+ are synthesized by a high temperature solid-state method. The emitting color of Ca2PO4Cl:Ce3+, Tb3+ can be adjusted from blue to green with increasing the Tb3+ doping content. The energy transfer from Ce3+ to Tb3+ in Ca2PO4Cl has been validated, and proved to be a resonant type via a dipole-dipole interaction. The critical distance of energy transfer is calculated by the concentration quenching method, and about 1.77 nm. Ca2PO4Cl:Ce3+, Tb3+ has a broad excitation band in the near ultraviolet range, and produces green emission, therefore, it may have potential application as near ultraviolet convertible phosphor for white light emitting diodes.