Novel Broadband Excited and Linear Red‐Emitting Ba 2 Y ( BO 3 ) 2 Cl : Ce 3+ , Tb 3+ , Eu 3+ Phosphor: Luminescence and Energy Transfer

A series of Ce 3+ , Tb 3+ , Eu 3+ tri‐doped Ba 2 Y ( BO 3 ) 2 Cl red‐emitting phosphor have been synthesized by solid‐state method. The Ce 3+ → Tb 3+ → Eu 3+ energy‐transfer scheme has been proposed to realize the sensitization of Eu 3+ ion emission by Ce 3+ ions. Following this energy‐transfer model, near‐ UV convertible Eu 3+ ‐activated red phosphors have been obtained in Ba 2 Y ( BO 3 ) 2 Cl : Ce 3+ , Tb 3+ , Eu 3+ phosphors. Energy transfers from Ce 3+ to Tb 3+ , and Tb 3+ to Eu 3+ , as well as corresponding energy‐transfer efficiencies are investigated. The combination of narrow‐line red emission and near‐ UV broadband excitation makes Ba 2 Y ( BO 3 ) 2 Cl : Ce 3+ , Tb 3+ , Eu 3+ as a novel and efficient red phosphor for NUV LED applications.