Formation and spectral probing of transparent oxyfluoride glass-ceramics containing (Eu2+, Eu3+:BaGdF5) nano-crystals

Enhanced near‐infrared to green upconversion from Er3+‐doped oxyfluoride glass and glass ceramics containing BaGdF5 nanocrystals

“…The emission spectra show similar spectral profile for both the glasses while an increase in the emission intensity of the broad-band emission ranging from 320 to 650 nm is observed upon ceramization. Similar broad emission band in oxyfluoride glass/glass ceramics has been reported in Eu 3+/ Eu 2+ -doped systems by our group 14,19 , and the origin of the broad band was attributed to the transition from 4f to 5d level of Eu 2+ ions. As the present systems do not contain any europium as dopants, the contributing effect of the broad-band emission could also be from defect centers present inside glasses.…”

“…For all the samples, sharp excitation bands at 356, 363, 378, 406, 443,450, 486, and 522 nm are observed due to transitions from ground state to 4 G 9/2 , 4 G 11/2 , ( 2 G, 4 F, 2 H) 9/2 , 4 F 5/2 , 4 F 7/2 , 2 H 11/2 , 4 S 3/2 energy levels of Er 3+ ions, respectively. Similar broad emission band in oxyfluoride glass/glass ceramics has been reported in Eu 3+/ Eu 2+ -doped systems by our group 14,19 , and the origin of the broad band was attributed to the transition from 4f to 5d level of Eu 2+ ions. Additionally, in the BaGdFG glass and BaGdFGC glass ceramics, the presence of excitation bands at 275 and 311 nm resulting from 6 I J and 6 P 7/2 levels of Gd 3+ ions, respectively, indicates energy transfer process from Gd 3+ to Er 3+ .…”

“…Huang and Gu 11 reported using Tb 3+ -doped oxyfluoride glass ceramics containing BaGdF 5 nanocrystals, Ce 3+ singly and Ce 3+/ Tb 3+ -co-doped systems by Wang et al, 12 and Eu 2+ -doped glass ceramics containing BaGdF 5 nanocrystals by Zhang et al 13 Recently, our group has studied the local structure around rare earth ions in oxyfluoride glass ceramics containing BaGdF 5 nanocrystals using Eu 3+ as spectral probe. 14 As a continuation, this work deals with a thorough investigation on luminescence characteristics of Er 3+ -doped transparent glass and glass ceramics containing BaGdF 5 nanocrystals.…”

Bright luminescence of Gd3+ sensitized RE3+-doped SiO2-BaGdF5 glass-ceramics for UV-LEDs colour conversion

“…Biswas et al [34] (around 12 nm), W. Zhang et al [8] (around 10-20 nm), P. Karmakar et al [44] (around 8-12 nm), Q. Wang et al [45] (around 13-28 nm) and S. Huang et at [35] (around 18-27 nm), in BaGdF 5 nGCs. It is worth mentioning that all nGCs present a high degree of transparency due to the fact that precipitated NC sizes are smaller than the wavelength of the visible light.…”

“…On the other hand, there are only a few reports about photo-luminescent properties of gadolinium fluoride based nGCs, where most of them have been prepared by a meltquenching method [8,10,[33][34][35][36][37][38]. In this respect, a different method to obtain nGCs is by thermal treatment of precursor glasses synthesised by a sol-gel technique.…”