Photoluminescence properties of red phosphor Gd3PO7:Eu3+ for UV-pumped light-emitting diodes

A red-emitting Gd3PO7:5% Eu3+ phosphor is reported. Through transitions of 5d → 4f (7F1 and 7F2) in Eu3+, the phosphor shows a bright red emission under ultraviolet (UV) light excitation. The emission intensity at 615 nm corresponding to 5D0 → 7F2 transition of Eu3+ ion depending on irradiation time under 394 nm excitation increases firstly and then small reduces. After 20 min for UV-light irradiation, it decreases by about 0.5% suggesting that the photostability of the red phosphor Gd3PO7:Eu3+ is excellent. Under 325 nm excitation, the emission intensities grow rapidly as the temperature increases from 75 K to 285 K and then it keeps on growing slowly until 475 K, revealing the excellent thermostability of the red phosphor Gd3PO7:Eu3+. Decay time and time-resolved luminescence measurements have also been studied. All the results reveal that Gd3PO7:Eu3+ is a promising red-emitting phosphor for UV LED applications.