Effect of tin ions on enhancing the intensity of narrow luminescence line at 311 nm of Gd3+ ions in Li2OPbOP2O5 glass system

Abstract This study is mainly focused on enriching the UVB 311 narrow emission band of Gd 3+ ions in Li 2 O PbO P 2 O 5 glasses doped with 1.0 mol% of Gd 2 O 3 and mixed with different concentrations of SnO 2 (0–7.0 mol%). The emission spectra SnO 2 free glasses exhibited intense narrow UVB band at 311 nm due to 6 P 7/2  →  8 S 7/2 transition of Gd 3+ ions when excited at 273 nm. The intensity of this band is found to be enhanced nearly four times when the glasses are mixed with 3.0 mol% of SnO 2 . The reasons for this enhancement have been explored in the light of energy transfer from Sn 4+ to Gd 3+ ions with the help of rate equations. The declustering of Gd 3+ ions (that reduce cross relaxation losses) by tin ions is also found to the other reason for such enrichment. The 311 nm radiation is an efficient in the treatment of various skin diseases and currently it is one of the most desirable and commonly utilised UVB in the construction of phototherapy devices.