Green/red photoluminescence emission in γ-Zn3(PO4)2:Mn2+/Ga3+ for applications in ultraviolet-light emitting diodes

In this Letter, γ-Zn3(PO4)2:Mn2+ phosphors have only one emission band centered at 620 nm while two emission bands are observed in γ-Zn3(PO4)2:Mn2+, Ga3+, which are respectively centered at 507 nm and 620 nm. The spectral overlap between the green emission band and the excitation band monitored at 620 nm, which supports the occurrence of the energy transfer from Mn2+ (CN = 4) to Mn2+ (CN = 6), has been studied. The distribution of Mn2+ ions in tetrahedral and octahedral lattice changes with the incorporation of Ga3+ ions. The ratio of the green to the red enhances because of the increase of both Ga3+ and Mn2+ concentration.