Improvement of the Luminescence of Red LaPO4:Eu Nanophosphors for a Near-UV LED

摘要

The luminescence of LaPO4:Eu phosphors was improved by coprecipitation with phosphate from different sources and with anionic surfactants. The effects of the method of synthesis on the characteristics of the phosphors were investigated. When H3PO4 was used as the source of phosphate, strong absorption of the charge transfer band (CTB) was observed. A red shift of the CTB absorption was observed when (NH4)(2)HPO4 and Na5P3O10 were used as sources of phosphate. Phosphors with high crystallographic symmetry of Eu3+ in the lattice were synthesized when (NH4)(2)HPO4 was used. The optimum crystallinity and the maximum photoluminescence (PL) intensity were obtained when the phosphor surface was modified with 1 mol.% (NaPO3)(6) and 3 mol.% sodium dodecyl sulfate (SDS) surfactant, with PL intensity being increased by 10% and 7%, respectively.