Comparative study on luminescent properties of LiLa ₂BO ₅:Eu ³⁺ phosphors synthesized with different methods

Motivated by the need for new red phosphors for solid-state lighting applications Eu ³⁺-doped LiLa ₂BO ₅ phosphor was synthesized with two methods: sol-gel (SG) and conventional solid-state reaction (SS) method. The synthesized deep red phosphor was characterized by XRD, PL and SEM, respectively. The phosphor has two main excitation peaks located at 395 and 468 nm, which match the emission of UV and blue LED, respectively. The emission intensity increased with increasing Eu ³⁺ concentration, and then decreased due to concentration quenching. The intensity of the sol-gel (SG) derived phosphor by monitoring at the excitation wavelength of 395 nm is about 80% of solid-state derived phosphor. In comparison with the commercial red phosphor (CaS:Eu ²⁺), our synthesized LiLa ₂BO ₅:Eu phosphor shows higher PL intensity, when excited with 468 nm light. The intense red emission of LiLa ₂BO ₅ under 395 and 468 nm excitation suggests that this phosphor is promising candidate as red-emitting phosphor for near-UV/blue-GaN based light-emitting diodes for white light generation.