Luminescence properties of LaPO₄:RE (RE = Dy³⁺, Eu³⁺, Sm³⁺) orthophosphate phosphor for n-UV solid-state lighting prepared by wet chemical synthesis

Abstract

The synthesis of LaPO₄:RE (RE = Dy³⁺, Eu³⁺, Sm³⁺) via a wet chemical method was reported. The prepared phosphor was characterized by XRD, and photoluminescence characteristics were reported. A monoclinic phase was confirmed by X-ray diffraction measurements. Under UV excitation (349 nm), LaPO₄:Dy³⁺ phosphor shows emission at 481 and 575 nm, corresponding to a magnetic dipole (⁴F_9/2 → ⁶H_15/2 ) and electric dipole (⁴F_9/2 → ⁶H_13/2) transitions. When LaPO₄:Eu³⁺ phosphor was stimulated at 394 nm, observed emission spectra exhibited prominent bands at 593 and 615 nm, corresponding to magnetic dipole ⁵D₀ → ⁷F₁ transition with the maximum intensity of emission and electric dipole ⁵D₀ → ⁷F₂ transition, respectively. When excited at a wavelength of 402 nm, the LaPO₄:Sm³⁺ phosphor shows emission at 562 nm and 597 nm, which correspond to the ⁴G_5/2→⁶H_5/2 and ⁴G_5/2→⁶H_7/2 transitions. The photoluminescence studies show that the LaPO₄:RE (RE = Dy³⁺, Eu³⁺ and Sm³⁺) phosphors could be applicable in the fields of n-UV-excited solid-state lighting.