Narrowband ultraviolet B emitting Gd3+ activated NaSrPO4 phosphor prepared by co-precipitation method

Sodium strontium phosphate or NaSrPO4 phosphor activated with gadolinium (Gd3+) was prepared by co-precipitation method. The X-ray diffraction (XRD) pattern confirmed that the phosphor crystallized in a monoclinic phase of NaSrPO4. The Fourier transform infrared spectroscopy (FTIR) data confirmed that the stretching mode frequencies were related to stretching vibrations of (PO4)(3-) group. The photoluminescence emission spectrum showed characteristic emissions of Gd3+ at 313 nm (P-6(7/2)-> S-8(7/2)). The EPR spectrum of gadolinium activated NaSrPO4 phosphor exhibited resonance signals at effective values of g approximate to 5.95, 4.90 and 2.02 indicating the existence gadolinium in trivalent state in the NaSrPO4 phosphor matrix.