Red Long Lasting Phosphorescence of Mn2+ Doped Zinc Phosphate Glasses

Mndoped ZnO-POglasses emit red fluorescence,which shows that Mnion doped in zinc phosphate glass is octahedrally coordinated.Moreover,glass samples exhibit bright red long lasting phosphorescence (LLP) when the mole percent of ZnO are more than 60%.After turnoff the irradiation source of UV lamp peaking at 254 nm,the red phosphorescence can be observed for about 6 h in the limit of light perception for naked eyes (0.32 mcd/m~2).Photoluminescence (PL) spectra,LLP emission spectra and decay curves were detected.Increasing MnO or ZnO content,the phosphorescence intensity can be improved distinctly and the emission wavelength can be also adjusted from 595 nm to 628 nm.According to the structural characteristic of zinc phosphates glasses,we suggest that non-bridge oxygen (NBO) is probably related with the arising of LLP.Meantime,the variation of crystal field intensity induced that the LLP emission wavelength red shifts.