Improvement of Photoluminescence Properties in YPO₄:Mn²⁺ Phosphor Codoped with Tetravalent cations

Abstract

Photoluminescence (PL) of YPO₄:Mn²⁺ codoped with four tetravalent cations (Zr⁴⁺, Sn⁴⁺, Ti⁴⁺, and Si⁴⁺) has been investigated at room temperature under excitation with vacuum ultraviolet (VUV) photons at 147 nm. The wavelength is located at the fundamantal absorption edge of YPO₄. The concentration of all the cations was set to be 1.0 mol% in preparation. The PL spectra exhibited a blue-green (BG) band peaking at 482 nm. The PL intensity of the BG band is highest when Zr⁴⁺ ions were codoped into YPO₄:Mn²⁺, and thus Zr⁴⁺-codoping is the best choice for PL enhancement in YPO₄:Mn²⁺ phosphors. It was found that the PL intensity of Zr⁴⁺ doped YPO₄:Mn²⁺ reached 80% of that of a well-known VUV phosphor BaMgAl₁₀O₁₇:Eu²⁺, unless the concentration of Mn²⁺ and Zr⁴⁺ ions was not optimaized.