- Email: [email protected]
Luminescence properties of Tb3+-doped oxyfluoride scintillating glasses
Journal of Luminescence 152 (2014) 241–243
Contents lists available at ScienceDirect
Journal of Luminescence journal homepage: www.elsevier.com/locate/jlumin
Luminescence properties of Tb3 þ -doped oxyfluoride scintillating glasses Shijie Jia, Lihui Huang n, Donglei Ma, Zhenxing Tai, Shilong Zhao, Degang Deng, Huanping Wang, Guohua Jia, Youjie Hua, Qinghua Yang, Shiqing Xu College of Materials Science and Engineering, China Jiliang University, Hangzhou 310018, China
art ic l e i nf o
a b s t r a c t
Available online 25 December 2013
Transparent oxyfluoride glasses doped with Tb3 þ were prepared by melt quenching method. The transmittance spectra show the glasses have good transmittance in the visible spectrum region. The emission spectra under 376 nm light and X-ray excitations were recorded. Tb3 þ doped oxyfluoride glasses show intense green emissions under both excitations. The optimum concentrations of Tb3 þ ion are around 8 mol% and around 10 mol% under 376 nm light excitation and X-ray excitation, respectively. The lifetimes of 541 nm emission of oxyfluoride glasses doped with Tb3 þ are in the range from 2.65 ms to 3.02 ms. The results indicate that Tb3 þ -doped oxyfluoride glasses could be an X-ray scintillating material suitable to X-ray detection for slow event. & 2013 Elsevier B.V. All rights reserved.
Keywords: Luminescence Tb3 þ Scintillating Oxyfluoride glass
1. Introduction Glass is an attractive scintillating material due to its advantages [1]. With respect to scintillating crystal, the advantages include low production cost, easy shaping of elements, possibility to incorporate activator ions at high concentrations and in the ease of manufacture in different sizes and shapes, such as fibers [2–4]. Researchers began to work on scintillating glasses during the late 1950s and early 1960s. Cerium-activated lithium-containing glass scintillators were developed by Spowart et al., which were used to detect neutrons [5,6]. Then in the 1990s, a new kind of terbiumactivated glass was reported [7]. Tb3 þ -doped silicate glass scintillator usually has higher emission intensity than that of Eu3 þ - or Ce3 þ -doped one [8], and the most intense emission of Tb3 þ is around 540 nm, which is convenient for a direct coupling with silicon detector. Consequently, it is useful for the detection of slow neutron and the X-ray scintillation screen [9–11]. Therefore, Tb3 þ doped silicate glass scintillator is a hot research topic in RE-doped scintillating materials. So far, many efforts have been devoted to researching on the luminescence properties of scintillating glasses [12–16]. Compared with the other kinds of glasses, oxyfluoride glasses can provide a desirable low phonon energy environment of fluoride for activator ions, which results in an increased radiative emission rate of the incorporated rare-earth ions, and maintain the advantages of an
n
Corresponding author. Tel.: þ 86 571 86835781. E-mail addresses: [email protected], [email protected] (L. Huang), [email protected] (S. Xu). 0022-2313/$ - see front matter & 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.jlumin.2013.12.036
oxide glass at the same time, such as high mechanical strength, chemical durability, and thermal stability [16,17] Therefore, much attention has paid to RE-doped oxyfluoride glasses. Recently, we developed Tb-doped oxyfluoride glasses successfully by a melt quenching method. Optical transmission, photoluminescence (PL), X-ray excited luminescence (XEL) and fluorescence decay properties of the glasses were investigated.
2. Experimental Tb3 þ -doped oxyfluoride glasses with the compositions of 45SiO2–10Al2O3–25BaO–(20 x)BaF2–xTbF3 (x ¼1, 2, 4, 6, 8, 10, 12, 15) (mol%) were prepared from high purity (99.99%) SiO2, Al2O3, BaCO3, BaF2, and TbF3. The raw materials were mixed thoroughly and melted in a covered alumina crucible at 1450 1C for 30 min in an electric furnace in the ambient atmosphere. Then the melt was poured into a preheated stainless steel mould and annealed for 2 h below the glass transition temperature and cooled down to room temperature at a rate of 0.5 1C/min. The glass samples were polished for optical measurements with a thickness of 1.50 70.02 mm. The transmittance spectra of the glass samples were recorded with a Shimadzu UV-3600 spectrophotometer in the range of 280– 840 nm. Photoluminescence (PL) spectra and luminescence decay curves were recorded on a Jobin-Yvon Fluorolog3 fluorescence spectrophotometer using Xe lamp as an excitation source. X-ray excited luminescence (XEL) spectra were performed by a X-ray excited spectrometer, where an F-30 X-ray tube (W anticathode target) was the X-ray source, operated under 70 kV and 6 mA.
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Fig. 1. Transmittance spectra of oxyfluoride glasses doped with different concentrations of Tb3 þ .
emissions have same tendency with increasing concentration of Tb3 þ . However, the intensities of 412 nm, 434 nm and 457 nm emissions decrease monotonically with increasing concentration of Tb3 þ . The behavior could be interpreted as follows. Since the energy difference between 5D3 level and 5D4 level is very close to that between 7F6 level and 7F0 level, the cross relaxation 5 D3 þ 7F6-5D4 þ 7F0 between two Tb3 þ ions could occur when Tb3 þ ion is very close to another Tb3 þ ion due to high concentration of Tb3 þ [21–23]. Thus the population of 5D3 level decreases and that of 5D4 level increases. This results in the intensities of the emissions (412 nm, 434 nm, and 457 nm) originated the transitions from 5D3 level to lower 7F levels decrease and the intensities of the emissions (487 nm, 582 nm, and 620 nm) from 5D4 level to lower 7F levels increase. Fig. 3 shows the excitation spectra of oxyfluoride glasses doped with different Tb3 þ concentrations by monitoring the green emission at 541 nm. It exhibits characteristic absorptions of Tb3 þ , which are consistent with those shown in Fig. 1. The strongest excitation band is around 376 nm, which is associated with the transition from the ground state 7F6 to 5D3 of Tb3 þ , while the weak bands located at 303 nm, 317 nm, 351 nm and 484 nm are assigned to the transitions from the ground state 7F6 to 5H6, 5 H7, 5D2, 5D4 states. In addition, the intensity of the excitation band increases with increasing concentration of Tb3 þ up to 8 mol%, then decreases. This is consistent with the emission spectra results. Fig. 4 shows the XEL spectra of oxyfluoride glasses doped with different Tb3 þ concentrations. The spectra are very similar to those excited by 376 nm light, except that an emission band with peak at 376 nm was also recorded. In XEL spectra, the emission at 541 nm is the strongest. Similarly, it is obviously seen that the green emissions of Tb3 þ increase with the increment of Tb3 þ concentration from 1 mol% to 10 mol%. However, the Tb3 þ emission intensity decreases when Tb3 þ concentration is more than 10 mol% due to the concentration quenching. And the intensities of the emissions at 376 nm, 412 nm, and 434 nm decrease monotonically with increasing Tb3 þ concentration. The results also could be interpreted with the luminescence mechanism of the cross relaxation mentioned before. The luminescence decay curves of 541 nm emission of Tb3 þ doped oxyfluoride glasses upon excitation of 376 nm light were recorded. All the curves are single exponential. The decay curve of oxyfluoride glass doped with 8 mol% Tb3 þ is shown in Fig. 5. The lifetime of 541 nm emission determined by the least-squares fitting of the decay curve with a single-exponential function is 2.817 0.03 ms. Inset in Fig. 5 shows the lifetimes of the 541 nm emission of the samples in the range from 2.65 ms to 3.02 ms with
Fig. 2. Emission spectra of oxyfluoride glasses doped with different concentrations of Tb3 þ upon an excitation of 376 nm light.
Fig. 3. Excitation spectra of oxyfluoride glasses doped with different concentrations of Tb3 þ , monitored at 541 nm.
3. Results and discussion Fig. 1 shows the transmittance spectra of oxyfluoride glasses doped with different concentrations of Tb3 þ . It shows that the glasses have good transmittance in the visible spectrum region. The UV cut-off wavelength is around 300 nm. The results indicate the glasses are suitable to be used as scintillator material. The spectra also show the absorption bands of Tb3 þ ions centered at 351 nm, 368 nm, 376 nm, 484 nm, which are assigned to the transitions from the ground state 7F6 to the higher 5D states of Tb3 þ . Under UV light, Tb3 þ -doped oxyfluoride glasses emit intense green light. It is consistent with Fu0 s report [18]. In the report, they demonstrated that the introduction of fluorine can result in an increase in the emission intensity. It is also an advantage of RE doped oxyfluoride glasses over RE doped oxide glasses [19,20]. Fig. 2 shows the emission spectra of the oxyfluoride glasses doped with different Tb3 þ concentrations with the excitation of 376 nm light. The spectra consist of six emission bands centered at 412 nm, 434 nm, 487 nm, 541 nm (a shoulder peak at 547 nm), 582 nm (a shoulder peak at 589 nm), and 620 nm, which are attributed to 5 L10 þ 5G6 þ 5D3-7F5, 5L10 þ 5G6 þ 5D3-7F4, 5D4-7F6, 5D4-7F5, 5 D4-7F4, and 5D4-7F3 transitions of Tb3 þ , respectively. Among them, the emission at 541 nm is the strongest. The intensity of 541 nm emission increases with increasing Tb3 þ concentration up to 8 mol%, then decreases due to concentration quenching. Thus, the optimum concentration of Tb3 þ in the oxyfluoride glass is around 8 mol%. Meanwhile 487 nm, 582 nm, and 620 nm
S. Jia et al. / Journal of Luminescence 152 (2014) 241–243
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376 nm light excitation and X-ray excitation, respectively. The lifetimes of 541 nm emission of oxyfluoride glasses doped with Tb3 þ are in the range from 2.65 ms to 3.02 ms. The results indicate that Tb3 þ -doped oxyfluoride glasses could be an X-ray scintillating material suitable to X-ray detection for slow event.
Acknowledgements
Fig. 4. XEL spectra of oxyfluoride glasses doped with different concentrations of Tb3 þ under the excitation of X-ray.
This work was financially supported by the National Natural Science Foundation of China (Grant Nos. 11375166 and 51272243), the Ministry of Human Resources and Social Security of the People0 s Republic of China (Merit-based Funding for Scientific and Technological Activities of Returned Overseas Scholars), and the Key Science and Technology Innovation Team of Zhejiang Province (No. 2010R50016).
References
Fig. 5. Decay curve of 541 nm emission in the sample with Tb3 þ concentration of 8 mol% upon excitation of 376 nm light. Inset: the lifetime dependence of 541 nm emission on Tb3 þ concentration.
different Tb3 þ concentrations. The results show the lifetime decreases monotonically with increasing Tb3 þ concentration. 4. Conclusions Transparent oxyfluoride glasses doped with Tb3 þ were prepared by melt quenching method. There is a strong broad UV absorption band which is beneficial for the 541 nm emission of Tb3 þ . Tb3 þ doped oxyfluoride glasses show intense green emission under both UV and X-ray excitations. The optimum concentrations of Tb3 þ ion are around 8 mol% and around 10 mol% under
[1] S. Baccaro, A. Cevilia, A. Cemmi, G. Chen, E. Mihokova, N. Nikl, IEEE Trans. Nucl. Sci. NS-48 (2001) 360. [2] M.J. Weber, J. Lumin. 100 (2002) 35. [3] G.P. Pazzi, P. Fabeni, C. Susini, M. Nikl, E. Mihokova, N. Solovieva, K. Nitsch, M. Martini, A. Vedda, S. Baccaro, A. Cevilia, V. Babin, Nucl. Instrum. Methods B 191 (2002) 366. [4] J. Fu, M. Kobayashi, J.M. Parker, J. Lumin. 128 (2008) 99. [5] A.R. Spowart, Nucl. Instrum. Methods 135 (1976) 441. [6] A.R. Spowart, Nucl. Instrum. Methods 140 (1977) 19. [7] G.B. Spector, T. McCollum, A.R. Spowart, Nucl. Instrum. Methods A 326 (1999) 526. [8] C. Bueno, R.A. Buchanan, SPIE 1327 (1990) 79. [9] G. Zanella, R. Zannoni, R. Dall’Igna, P. Polato, M. Bettinelli, Nucl. Instrum. Methods A 359 (1995) 547. [10] S. Baccaro, R. Dall’Igna, P. Fabeni, M. Martini, J.A. Mares, F. Meinardi, M. Nikl, K. Nitsch, G.P. Pazzi, P. Polato, C. Susini, A. Vedda, G. Zanella, R. Zannoni, J. Lumin. 87–89 (2003) 673. [11] J.A. Mares, M. Nikl, K. Nitsch, N. Solovieva, A. Krasnikov, S. Zazubovich, J. Lumin. 94–95 (2001) 321. [12] J.H. Campbell, T.I. Suratwala, J. Non-Cryst. Solids 263–264 (2000) 318. [13] S. Baccaro, A. Cecilia, M. Montecchi, M. Nikl, P. Polato, G. Zanella, R. Zannoni, J. Non-Cryst. Solids 315 (2003) 271. [14] B. Baumbaugh, J. Bishop, J. Busenitz, N. Cason, J. Cunningham, R. Gardner, E. Mannel, R.J. Mountain, D. Puseljic, R. Ruchti, W. Shephard, IEEE Trans. Nucl. Sci. NS-34 (1987) 541. [15] E. Auffray, D. Bouttet, I. Dafinei, J. Fay, P. Lecoq, J.A. Mares, M. Martini, G. Maze, F. Mernardi, B. Moine, M. Nikl, C. Pedrini, M. Poulain, M. Schneegans, S. Tavernier, A. Vedda, Nucl. Instrum. Methods A 380 (1996) 524. [16] Z. Pan, K. James, Y. Cui, A. Burger, N. Cherepy, S.A. Payne, R. Mu, S.H. Morgan, Nucl. Instrum. Methods A 594 (2008) 215. [17] Z. Pan, A. Ueda, S.H. Morgan, R. Mu, J. Rare Earths 24 (2006) 699. [18] J. Fu, M. kobayashi, J.M. Parker, J. Lumin. 128 (2008) 99. [19] C.G. Zuo, A.X. Lu, L.G. Zhu, Mater. Sci. Eng., B 175 (2010) 229. [20] Y.B. Zhang, Z.F. Zhu, W.J. Zhang, Y.P. Qiao, J. Alloys Compd. 566 (2013) 164. [21] T. Tsuboi, Eur. Phys. J. Appl. Phys. 26 (2004) 95. [22] G. Blasse, B.C. Grabmaier, Luminescent Materials, Springer-Verlag, Berlin, 1994. [23] D.B. He, C.L. Yu, J.M. Cheng, S.H. Li, L. Hu, J. Alloys Compd. 509 (2011) 1906.
Contents lists available at ScienceDirect
Journal of Luminescence journal homepage: www.elsevier.com/locate/jlumin
Luminescence properties of Tb3 þ -doped oxyfluoride scintillating glasses Shijie Jia, Lihui Huang n, Donglei Ma, Zhenxing Tai, Shilong Zhao, Degang Deng, Huanping Wang, Guohua Jia, Youjie Hua, Qinghua Yang, Shiqing Xu College of Materials Science and Engineering, China Jiliang University, Hangzhou 310018, China
art ic l e i nf o
a b s t r a c t
Available online 25 December 2013
Transparent oxyfluoride glasses doped with Tb3 þ were prepared by melt quenching method. The transmittance spectra show the glasses have good transmittance in the visible spectrum region. The emission spectra under 376 nm light and X-ray excitations were recorded. Tb3 þ doped oxyfluoride glasses show intense green emissions under both excitations. The optimum concentrations of Tb3 þ ion are around 8 mol% and around 10 mol% under 376 nm light excitation and X-ray excitation, respectively. The lifetimes of 541 nm emission of oxyfluoride glasses doped with Tb3 þ are in the range from 2.65 ms to 3.02 ms. The results indicate that Tb3 þ -doped oxyfluoride glasses could be an X-ray scintillating material suitable to X-ray detection for slow event. & 2013 Elsevier B.V. All rights reserved.
Keywords: Luminescence Tb3 þ Scintillating Oxyfluoride glass
1. Introduction Glass is an attractive scintillating material due to its advantages [1]. With respect to scintillating crystal, the advantages include low production cost, easy shaping of elements, possibility to incorporate activator ions at high concentrations and in the ease of manufacture in different sizes and shapes, such as fibers [2–4]. Researchers began to work on scintillating glasses during the late 1950s and early 1960s. Cerium-activated lithium-containing glass scintillators were developed by Spowart et al., which were used to detect neutrons [5,6]. Then in the 1990s, a new kind of terbiumactivated glass was reported [7]. Tb3 þ -doped silicate glass scintillator usually has higher emission intensity than that of Eu3 þ - or Ce3 þ -doped one [8], and the most intense emission of Tb3 þ is around 540 nm, which is convenient for a direct coupling with silicon detector. Consequently, it is useful for the detection of slow neutron and the X-ray scintillation screen [9–11]. Therefore, Tb3 þ doped silicate glass scintillator is a hot research topic in RE-doped scintillating materials. So far, many efforts have been devoted to researching on the luminescence properties of scintillating glasses [12–16]. Compared with the other kinds of glasses, oxyfluoride glasses can provide a desirable low phonon energy environment of fluoride for activator ions, which results in an increased radiative emission rate of the incorporated rare-earth ions, and maintain the advantages of an
n
Corresponding author. Tel.: þ 86 571 86835781. E-mail addresses: [email protected], [email protected] (L. Huang), [email protected] (S. Xu). 0022-2313/$ - see front matter & 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.jlumin.2013.12.036
oxide glass at the same time, such as high mechanical strength, chemical durability, and thermal stability [16,17] Therefore, much attention has paid to RE-doped oxyfluoride glasses. Recently, we developed Tb-doped oxyfluoride glasses successfully by a melt quenching method. Optical transmission, photoluminescence (PL), X-ray excited luminescence (XEL) and fluorescence decay properties of the glasses were investigated.
2. Experimental Tb3 þ -doped oxyfluoride glasses with the compositions of 45SiO2–10Al2O3–25BaO–(20 x)BaF2–xTbF3 (x ¼1, 2, 4, 6, 8, 10, 12, 15) (mol%) were prepared from high purity (99.99%) SiO2, Al2O3, BaCO3, BaF2, and TbF3. The raw materials were mixed thoroughly and melted in a covered alumina crucible at 1450 1C for 30 min in an electric furnace in the ambient atmosphere. Then the melt was poured into a preheated stainless steel mould and annealed for 2 h below the glass transition temperature and cooled down to room temperature at a rate of 0.5 1C/min. The glass samples were polished for optical measurements with a thickness of 1.50 70.02 mm. The transmittance spectra of the glass samples were recorded with a Shimadzu UV-3600 spectrophotometer in the range of 280– 840 nm. Photoluminescence (PL) spectra and luminescence decay curves were recorded on a Jobin-Yvon Fluorolog3 fluorescence spectrophotometer using Xe lamp as an excitation source. X-ray excited luminescence (XEL) spectra were performed by a X-ray excited spectrometer, where an F-30 X-ray tube (W anticathode target) was the X-ray source, operated under 70 kV and 6 mA.
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S. Jia et al. / Journal of Luminescence 152 (2014) 241–243
Fig. 1. Transmittance spectra of oxyfluoride glasses doped with different concentrations of Tb3 þ .
emissions have same tendency with increasing concentration of Tb3 þ . However, the intensities of 412 nm, 434 nm and 457 nm emissions decrease monotonically with increasing concentration of Tb3 þ . The behavior could be interpreted as follows. Since the energy difference between 5D3 level and 5D4 level is very close to that between 7F6 level and 7F0 level, the cross relaxation 5 D3 þ 7F6-5D4 þ 7F0 between two Tb3 þ ions could occur when Tb3 þ ion is very close to another Tb3 þ ion due to high concentration of Tb3 þ [21–23]. Thus the population of 5D3 level decreases and that of 5D4 level increases. This results in the intensities of the emissions (412 nm, 434 nm, and 457 nm) originated the transitions from 5D3 level to lower 7F levels decrease and the intensities of the emissions (487 nm, 582 nm, and 620 nm) from 5D4 level to lower 7F levels increase. Fig. 3 shows the excitation spectra of oxyfluoride glasses doped with different Tb3 þ concentrations by monitoring the green emission at 541 nm. It exhibits characteristic absorptions of Tb3 þ , which are consistent with those shown in Fig. 1. The strongest excitation band is around 376 nm, which is associated with the transition from the ground state 7F6 to 5D3 of Tb3 þ , while the weak bands located at 303 nm, 317 nm, 351 nm and 484 nm are assigned to the transitions from the ground state 7F6 to 5H6, 5 H7, 5D2, 5D4 states. In addition, the intensity of the excitation band increases with increasing concentration of Tb3 þ up to 8 mol%, then decreases. This is consistent with the emission spectra results. Fig. 4 shows the XEL spectra of oxyfluoride glasses doped with different Tb3 þ concentrations. The spectra are very similar to those excited by 376 nm light, except that an emission band with peak at 376 nm was also recorded. In XEL spectra, the emission at 541 nm is the strongest. Similarly, it is obviously seen that the green emissions of Tb3 þ increase with the increment of Tb3 þ concentration from 1 mol% to 10 mol%. However, the Tb3 þ emission intensity decreases when Tb3 þ concentration is more than 10 mol% due to the concentration quenching. And the intensities of the emissions at 376 nm, 412 nm, and 434 nm decrease monotonically with increasing Tb3 þ concentration. The results also could be interpreted with the luminescence mechanism of the cross relaxation mentioned before. The luminescence decay curves of 541 nm emission of Tb3 þ doped oxyfluoride glasses upon excitation of 376 nm light were recorded. All the curves are single exponential. The decay curve of oxyfluoride glass doped with 8 mol% Tb3 þ is shown in Fig. 5. The lifetime of 541 nm emission determined by the least-squares fitting of the decay curve with a single-exponential function is 2.817 0.03 ms. Inset in Fig. 5 shows the lifetimes of the 541 nm emission of the samples in the range from 2.65 ms to 3.02 ms with
Fig. 2. Emission spectra of oxyfluoride glasses doped with different concentrations of Tb3 þ upon an excitation of 376 nm light.
Fig. 3. Excitation spectra of oxyfluoride glasses doped with different concentrations of Tb3 þ , monitored at 541 nm.
3. Results and discussion Fig. 1 shows the transmittance spectra of oxyfluoride glasses doped with different concentrations of Tb3 þ . It shows that the glasses have good transmittance in the visible spectrum region. The UV cut-off wavelength is around 300 nm. The results indicate the glasses are suitable to be used as scintillator material. The spectra also show the absorption bands of Tb3 þ ions centered at 351 nm, 368 nm, 376 nm, 484 nm, which are assigned to the transitions from the ground state 7F6 to the higher 5D states of Tb3 þ . Under UV light, Tb3 þ -doped oxyfluoride glasses emit intense green light. It is consistent with Fu0 s report [18]. In the report, they demonstrated that the introduction of fluorine can result in an increase in the emission intensity. It is also an advantage of RE doped oxyfluoride glasses over RE doped oxide glasses [19,20]. Fig. 2 shows the emission spectra of the oxyfluoride glasses doped with different Tb3 þ concentrations with the excitation of 376 nm light. The spectra consist of six emission bands centered at 412 nm, 434 nm, 487 nm, 541 nm (a shoulder peak at 547 nm), 582 nm (a shoulder peak at 589 nm), and 620 nm, which are attributed to 5 L10 þ 5G6 þ 5D3-7F5, 5L10 þ 5G6 þ 5D3-7F4, 5D4-7F6, 5D4-7F5, 5 D4-7F4, and 5D4-7F3 transitions of Tb3 þ , respectively. Among them, the emission at 541 nm is the strongest. The intensity of 541 nm emission increases with increasing Tb3 þ concentration up to 8 mol%, then decreases due to concentration quenching. Thus, the optimum concentration of Tb3 þ in the oxyfluoride glass is around 8 mol%. Meanwhile 487 nm, 582 nm, and 620 nm
S. Jia et al. / Journal of Luminescence 152 (2014) 241–243
243
376 nm light excitation and X-ray excitation, respectively. The lifetimes of 541 nm emission of oxyfluoride glasses doped with Tb3 þ are in the range from 2.65 ms to 3.02 ms. The results indicate that Tb3 þ -doped oxyfluoride glasses could be an X-ray scintillating material suitable to X-ray detection for slow event.
Acknowledgements
Fig. 4. XEL spectra of oxyfluoride glasses doped with different concentrations of Tb3 þ under the excitation of X-ray.
This work was financially supported by the National Natural Science Foundation of China (Grant Nos. 11375166 and 51272243), the Ministry of Human Resources and Social Security of the People0 s Republic of China (Merit-based Funding for Scientific and Technological Activities of Returned Overseas Scholars), and the Key Science and Technology Innovation Team of Zhejiang Province (No. 2010R50016).
References
Fig. 5. Decay curve of 541 nm emission in the sample with Tb3 þ concentration of 8 mol% upon excitation of 376 nm light. Inset: the lifetime dependence of 541 nm emission on Tb3 þ concentration.
different Tb3 þ concentrations. The results show the lifetime decreases monotonically with increasing Tb3 þ concentration. 4. Conclusions Transparent oxyfluoride glasses doped with Tb3 þ were prepared by melt quenching method. There is a strong broad UV absorption band which is beneficial for the 541 nm emission of Tb3 þ . Tb3 þ doped oxyfluoride glasses show intense green emission under both UV and X-ray excitations. The optimum concentrations of Tb3 þ ion are around 8 mol% and around 10 mol% under
[1] S. Baccaro, A. Cevilia, A. Cemmi, G. Chen, E. Mihokova, N. Nikl, IEEE Trans. Nucl. Sci. NS-48 (2001) 360. [2] M.J. Weber, J. Lumin. 100 (2002) 35. [3] G.P. Pazzi, P. Fabeni, C. Susini, M. Nikl, E. Mihokova, N. Solovieva, K. Nitsch, M. Martini, A. Vedda, S. Baccaro, A. Cevilia, V. Babin, Nucl. Instrum. Methods B 191 (2002) 366. [4] J. Fu, M. Kobayashi, J.M. Parker, J. Lumin. 128 (2008) 99. [5] A.R. Spowart, Nucl. Instrum. Methods 135 (1976) 441. [6] A.R. Spowart, Nucl. Instrum. Methods 140 (1977) 19. [7] G.B. Spector, T. McCollum, A.R. Spowart, Nucl. Instrum. Methods A 326 (1999) 526. [8] C. Bueno, R.A. Buchanan, SPIE 1327 (1990) 79. [9] G. Zanella, R. Zannoni, R. Dall’Igna, P. Polato, M. Bettinelli, Nucl. Instrum. Methods A 359 (1995) 547. [10] S. Baccaro, R. Dall’Igna, P. Fabeni, M. Martini, J.A. Mares, F. Meinardi, M. Nikl, K. Nitsch, G.P. Pazzi, P. Polato, C. Susini, A. Vedda, G. Zanella, R. Zannoni, J. Lumin. 87–89 (2003) 673. [11] J.A. Mares, M. Nikl, K. Nitsch, N. Solovieva, A. Krasnikov, S. Zazubovich, J. Lumin. 94–95 (2001) 321. [12] J.H. Campbell, T.I. Suratwala, J. Non-Cryst. Solids 263–264 (2000) 318. [13] S. Baccaro, A. Cecilia, M. Montecchi, M. Nikl, P. Polato, G. Zanella, R. Zannoni, J. Non-Cryst. Solids 315 (2003) 271. [14] B. Baumbaugh, J. Bishop, J. Busenitz, N. Cason, J. Cunningham, R. Gardner, E. Mannel, R.J. Mountain, D. Puseljic, R. Ruchti, W. Shephard, IEEE Trans. Nucl. Sci. NS-34 (1987) 541. [15] E. Auffray, D. Bouttet, I. Dafinei, J. Fay, P. Lecoq, J.A. Mares, M. Martini, G. Maze, F. Mernardi, B. Moine, M. Nikl, C. Pedrini, M. Poulain, M. Schneegans, S. Tavernier, A. Vedda, Nucl. Instrum. Methods A 380 (1996) 524. [16] Z. Pan, K. James, Y. Cui, A. Burger, N. Cherepy, S.A. Payne, R. Mu, S.H. Morgan, Nucl. Instrum. Methods A 594 (2008) 215. [17] Z. Pan, A. Ueda, S.H. Morgan, R. Mu, J. Rare Earths 24 (2006) 699. [18] J. Fu, M. kobayashi, J.M. Parker, J. Lumin. 128 (2008) 99. [19] C.G. Zuo, A.X. Lu, L.G. Zhu, Mater. Sci. Eng., B 175 (2010) 229. [20] Y.B. Zhang, Z.F. Zhu, W.J. Zhang, Y.P. Qiao, J. Alloys Compd. 566 (2013) 164. [21] T. Tsuboi, Eur. Phys. J. Appl. Phys. 26 (2004) 95. [22] G. Blasse, B.C. Grabmaier, Luminescent Materials, Springer-Verlag, Berlin, 1994. [23] D.B. He, C.L. Yu, J.M. Cheng, S.H. Li, L. Hu, J. Alloys Compd. 509 (2011) 1906.