Spectroscopic properties Eu3+ doped and Tm3+/Yb3+ codoped oxyfluoride glass ceramics containing Ba2GdF7 nanocrystals

Transparent oxyfluoride glass ceramics

“…Further, the assignment of specific stoichiometric formulas or structures of ordered phases to the synthesized cubic solid solutions of varied composition, A c c e p t e d M a n u s c r i p t 29 such as Pb 4 Yb 3 F 17 :R 3+ [23], tweittite [307], BaYF 5 [109,101,102] or Ba 2 RF 7 [42,199,200,201], is not accurate. For example, Xin et al [43] and Bai et al [202] frivolously and arbitrarily assigned to the peaks of cubic phases, that correspond to M 1-x R x F 2+x solid solutions, some awkward Miller indexes taken from "Sr 2 GdF 7 " [43] and Ba 2 YbF 7 [202] X-ray diffraction patterns.…”

“…1200 o C for germinate or borate glasses. Preparation of glass ceramics from of aluminosilicate [35-A c c e p t e d M a n u s c r i p t 6 40], silicate [41], silicoborate [42][43][44], lead-silicate [45][46][47], quartz [48][49][50][51][52][53], lead-germanate [54][55][56], tellurate-germanate [57], zinc-tellurate [58], lithiumborate, potassium-borate, barium-borate [59,60], tungsten-lead-phosphate [61] and others glasses with high metal fluoride content is thoroughly described in the literature (see Table 1). …”

“…Thus, Sontakke and Annapurna [172] studied energy transfer kinetics for combinations of different donor-acceptor ions (e.g., Nd 3+ /Yb 3+ ; Yb 3+ /Dy 3+ ; Nd 3+ /Dy 3+ ) in cubic NaYF 4 nanoparticles; Lin et al [150] and Yu et al [95] studied Tm 3+ ions up-and down-conversion luminescence; and Wang and Ohwaki [19] were the first ones who achieved an up-conversion luminescence for Yb 3+ /Er 3+ ionic pair in fluoride glass ceramics (Pb 1-x Cd x F 2 -based nanoparticles) with energy transformation from the nearinfrared to the visible part of the spectrum. Later, the same activator couple was used in nanoparticles of different chemical compositions, such as PbF 2 [53,115,193], "Pb 4 Yb 3 F 17 " [23], CaF 2 [74,86,89,330], Ca 1-x La x F 2+x [68], SrF 2 [142], BaF 2 [230], "Ba 2 GdF 7 " [42,200], NaYF 4 [44], YOF [204], β-NaCaAlF 6 [96] and other [58] surrounded by oxide glass matrixes. The up-conversion luminescence for Yb 3+ /Tm 3+ ion pair in oxifluoride glass ceramics has been studied for PbF 2 [117,222], SrF 2 [138], "Ba 2 GdF 7 " [199], β-YF 3 [190] nanocrystals.…”

“…Later, the same activator couple was used in nanoparticles of different chemical compositions, such as PbF 2 [53,115,193], "Pb 4 Yb 3 F 17 " [23], CaF 2 [74,86,89,330], Ca 1-x La x F 2+x [68], SrF 2 [142], BaF 2 [230], "Ba 2 GdF 7 " [42,200], NaYF 4 [44], YOF [204], β-NaCaAlF 6 [96] and other [58] surrounded by oxide glass matrixes. The up-conversion luminescence for Yb 3+ /Tm 3+ ion pair in oxifluoride glass ceramics has been studied for PbF 2 [117,222], SrF 2 [138], "Ba 2 GdF 7 " [199], β-YF 3 [190] nanocrystals. Other achievements in this area include: an up-conversion luminescence of CaF 2 :Er 3+ , enhanced by plasmon resonance on gold nanoparticles, observed in [65]; an enhanced luminescence of nano-LaOF:Er 3+ observed in [205]; interaction of Tb 3+ -Yb 3+ co-activator couple in various fluoride nanoceramics [164,128,96].…”

Enhanced ~2μm and upconversion emission from Ho–Yb codoped oxyfluoride glass ceramics

“…By heating the oxyfluoride glass around the crystallization temperature for a period of time, transparent oxyfluoride glass ceramics can be fabricated, in which fluoride nanocrystals are dispersed in the oxide glass matrix. As doped rare earth ions are preferentially incorporated into crystalline phases with small phonon energies below 500 cm − 1 , rare earth ions doped glass ceramics will have strong luminescence emission [13,14]. However, there are few reports about 2 μm emission in oxyfluoride glass ceramics [15][16][17].…”