Self-crystallized novel transparent Na5Yb9F32: Er3+ glass-ceramics for optical thermometry and spectral conversion

Accepted Manuscript 3+ Self-crystallized novel transparent Na5Yb9F32: Er glass-ceramics for optical thermometry and spectral conversion Fangfang Hu, Jiangkun Cao, Xiantao Wei, Siqi Lu, Xinyue Li, Yanguang Qin, Hai Guo, Yonghu Chen, Changkui Duan, Min Yin PII:

S0925-8388(17)32170-9

DOI:

10.1016/j.jallcom.2017.06.171

Reference:

JALCOM 42240

To appear in:

Journal of Alloys and Compounds

Received Date: 2 December 2016 Revised Date:

13 June 2017

Accepted Date: 15 June 2017

Please cite this article as: F. Hu, J. Cao, X. Wei, S. Lu, X. Li, Y. Qin, H. Guo, Y. Chen, C. Duan, M. 3+ Yin, Self-crystallized novel transparent Na5Yb9F32: Er glass-ceramics for optical thermometry and spectral conversion, Journal of Alloys and Compounds (2017), doi: 10.1016/j.jallcom.2017.06.171. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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Self-crystallized novel transparent Na5Yb9F32: Er3+

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glass-ceramics for optical thermometry and spectral Fangfang Hu1, Jiangkun Cao3, Xiantao Wei1, Siqi Lu1, Xinyue Li4, Yanguang Qin1, Hai Guo2, Yonghu Chen1, Changkui Duan1,*, Min Yin1,* 1. Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, School of Physical Sciences, University of Science and Technology of China, No. 96 Jinzhai Road, Hefei, Anhui Province, 230026, P. R. China

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2. Department of Physics, Zhejiang Normal University, Jinhua, Zhejiang, 321004, China 3. South China Univeristy of Technology, School of Materials Science and Engineering

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4. College of Materials and Enviromental Engineering, Hangzhou Dianzi University, Hangzhou 310018, Chia

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ABSTRACT Novel self-crystallized transparent Na5Yb9F32: Er3+ glass-ceramics (GCs) were successfully elaborated through high temperature melt-quenching route for the first time. X-ray diffraction (XRD), transmission electron microscopy (TEM), selected-area electron diffraction (SAED) and photoluminescence emission spectra confirmed that the Na5Yb9F32 nanocrystals (NCs) were well-formed without any additional phase. In addition, X-ray photoelectron spectroscopy (XPS) was studied for investigating valence states of elements in the Na5Yb9F32: Er3+ GCs and it was suggesting that Er3+ ions was doped into the Na5Yb9F32: Er3+ GCs. Interestingly, the XRD patterns and TEM images demonstrate that the Na5Yb9F32 NCs have already formed during melt-quenching process without any further heat treatment. Due to improved crystallinity, reduced surface-to-volume ratio and more Er3+ incorporation into NCs after further heat treatment, both up-conversion (UC) and down-conversion (DC) show enhanced luminescence intensity after heat treatment. The emission color of Na5Yb9F32 GCs changed under different ultraviolet excitation wavelength was addressed and interpreted by photoluminescence. Furthermore, via the fluorescence intensity ratio (FIR), the temperature-dependent green UC emissions of Na5Yb9F32: Er3+ GCs were studied under 980 nm laser excitation. Provided with broad operating temperature range (300 - 773 K), large energy gap of thermal coupled energy levels (835 cm-1) and high sensitivity (1.33% K-1 at 300 K), the Na5Yb9F32: Er3+ GCs may have potential application in temperature senor. Keywords: Glass-ceramics; Na5Yb9F32: Er3+; Optical thermometry; Photoluminescence.

*Corresponding authors. Tel: +86 (551) 63606912; fax: +86 (551) 63600817. E-mail addresses: [email protected] (C.K. Duan), [email protected] (M. Yin)

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1. Introduction Over the past decades, there are numerous interests in inorganic luminescence materials doped with lanthanide ions because of their wide potential applications in lighting and displays, catalysis, biological labels, drug delivery carriers, and temperature sensors, among others [1-6]. Particularly, in recent years, the optical temperature sensors based on temperature-sensitive UC luminescence of the thermally coupled energy states has garnered considerable attentions owing to their unique advantages such as noncontact approach, low dependence on external factors, rapid response, high spatial and temperature resolutions, which is favorable for operating in harsh environments and detecting fast moving objects [7-9]. In order to acquire superior optical temperature sensing performance, such as wide temperature sensing range, high sensitivity, accuracy and stability, the host material is critically important. So far, plenty of attempts have been made in fluoride, oxide, ceramics, glass, metal-organic frameworks and so on. In these materials, the temperature sensing ability varies differently. Due to low phonon energy, fluoride can provide efficient UC luminescence which is benefit to the accuracy of spectrum measurement. However, its poor stability at high temperature will affect the repeatability in heat-cooling recycle. Oxide with high stability at high temperature will offer a wide temperature sensing range. Nevertheless, efficient UC luminescence cannot achieve in this matrix because of their high phonon energy. Transparent ceramics with favorable temperature sensing properties suffer from complex and high cost synthetic process. Account of high phonon energy and abundant defects acting as quenching centers, the luminescent centers cannot obtain desired luminescence in glass matrix. For metal-organic frameworks, inadequate stability at relative high temperature restricts its operating temperature to physiological temperature range [10-14]. Recently, oxyflouride glass ceramics (OXFGCs) have been examined as potential hosts for rare earth (RE) ions doping since that they combine the merits of low phonon energy of fluoride NCs and high thermal stability of oxide glasses [15]. Moreover, their positive ion valence state and ionic radius are befitting for RE ions doping, making them suitable hosts for highly efficient luminescence [16]. Up to now, Er3+ activator has been extensively explored in optical sensing due to the FIR of UC between 2 H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions of Er3+, which would greatly vary with temperature and consequently can act as an index of environment temperature. In addition, Yb3+ ion is usually doped as sensitizer in UC process to enhance the pump efficiency of Er3+ because of the large absorption cross section around 980 nm of Yb3+ and efficient energy transfer from Yb3+ to Er3+ [17-19]. Therefore, increasing attention has been paid to the UC properties of OXFGCs containing Yb-based fluoride NCs viz. KYb2F7, Sr2YbF7, LiYbF4, NaYbF4, BaYbF5, and all results evidenced that these GCs were excellent hosts for efficient UC. Accordingly, the investigation of UC properties of RE ions doped transparent Yb-based fluoride GCs is of great challenge and research value [20-24]. Herein, novel transparent Na5Yb9F32:Er3+ GCs were successfully fabricated through melt-quenching method. Moreover, we also systematically investigated the optical thermometry of Er3+ doped GCs. All results indicate that Er3+ doped Na5Yb9F32 GCs could be considered as potential candidates for temperature sensor and DC materials. 2. Experimental procedures The Er3+-doped precursor glass (PG) was elaborated with the following nominal composition (in mol %): 45 SiO2 - 16 Al2O3 - 15 Na2CO3 - 4 CaCO3 - 18 NaF - 4 YbF3 - 0.2 ErF3. The raw materials of SiO2 (AR), Al2O3 (AR), Na2CO3 (AR), CaCO3 (AR), NaF (AR) and high purity YbF3 (4N), ErF3 (4N) were thoroughly crashed and melted at 1500 °C for 1 h in air. Then the melt was poured into 300 °C preheated copped mold to form PG. Subsequently, the PG was heat treated at 680 °C for 2 h to form GCs, which labeled GC680.

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The XRD patterns, TEM, SAED, photoluminescence and the temperature dependence of emission spectrum emission were investigated based on the same experimental setup reported in our previous work [25]. All the measurements, except for figure 6, were carried out at room temperature.

kλ β cos θ

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3. Results and discussion 3.1. Analysis of the structure 3.1.1. XRD The formation of PG and GC680 were demonstrated by XRD patterns in Fig. 1 (a). The PG sample shows weak diffraction peaks over the two diffuse humps, which indicates that the NCs have already formed before heat treatment. It is available to access desirable NCs sizes and activators partition. After further heat treatment, the diffraction peaks in accordance with cubic Na5Yb9F32 NCs (JCPDS No. 27-1426) become intense, indicating increased crystallinity of self-crystallized NCs. The mean crystalline size D was estimated to 28 nm according to the following Scherrer’s equation [26],

(1)

where k = 0.89, θ is the Bragg angle of the X-ray diffraction peak, β represents the corrected full-width at

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half-maximum of the diffraction peak and λ (= 0.15418 nm) represents the wavelength of Cu Kα radiation. 3.1.2. Transmittance spectra Transmittance, an important parameter for GCs used as optical fiber sensors, was recorded between 240 1200 nm at room temperature. As depicted in Fig. 1 (b) the GC680 maintains 92% transmittance in long wavelength visible light range, indicating that the size of Na5Yb9F32: Er3+ NCs distributed homogeneously in glass matrix. A series of evident absorption peaks located at 375 nm, 405 nm, 450 nm, 486 nm, 520 nm, and 650 nm correspond to the transitions from the 4I15/2 multiplet state to 4G11/2, 2H9/2, 4F5/2, 4F7/2, 2H11/2 and 4F9/2 multiplet states of Er3+, respectively. The broad absorption band at around 973 nm can be mainly ascribed to the 2F7/2 → 2 F5/2 transition of Yb3+ ions, with strong absorption cross section around 980nm, accompanied by a weak 4I15/2 → 4 I11/2 transition of Er3+ [27]. 3.1.3. TEM, HRTEM and SAED For further visualization of the microstructures of the samples, TEM bright field images of the PG and GC680 were displayed in Fig. 1(c) and (e), respectively. From the TEM of PG sample in Fig.1(c), NCs with sizes of lower than 15 nm are obviously, confirming that self-crystallization in glass has occurred during melt-quenching process. After heat treatment at 680 °C for 2 h causes the mean sizes of these NCs grow up apparently up to 30 nm (Fig. 1 (e)), which is in accordance with the result calculated from the Scherrer’s equation. Notably, compared to HRTEM of PG in Fig. 1 (d), the HRTEM of GC680 in Fig. 1 (f) demonstrates that the crystallinity has been improved after heat treatment at 680 °C for 2 h. The SAED patterns [inset of Fig. 1(f)] of GC680 demonstrate the polycrystalline diffraction feature of the precipitated NCs. To summarize, the TEM, HRTEM, and SAED images further attested the formation of the cubic phase of Na5Yb9F32 GCs. 3.2. XPS The XPS technique was used in this study for investigating valence states of elements in Er3+ doped Na5Yb9F32 GC680 by means of photoelectron peaks connecting with binding energy. Fig. 2 (a) shows the XPS spectrum of the typical Er3+-doped Na5Yb9F32 GC680 with the glass matrix composition SiO2-Al2O3-Na2CO3-CaCO3. The

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XPS peaks show that the material contain only Si, Al, Ca, O, Na, Yb, F and Er and a trace amount of carbon. The Yb and Er XPS spectrum for the Na5Yb9F32: Er3+ GC680 is shown in Fig. 2 (b). In this spectrum, two main peaks are identified: Yb 4d at 186.17ev and Er 4d at 170.96 ev, in agreement with the handbook of x-ray photoelectron spectroscopy [28] and Sc3+/Er3+/Yb3+ tridoped NaYF4 [29]. As shown in Table 1, the atomic concentration of Er3+ and Yb3+ were detected by XPS. It was suggested that Er3+ ions was doped into the Na5Yb9F32: Er3+ GCs.

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3.3. Luminescence properties The doped Er3+ activators will prefer occupying Yb3+ sites in Na5Yb9F32 NCs due to their similar chemical properties, thus leading to spontaneous incorporation of Er3+ ions into the crystalline lattice of the NCs. It can be presumed that the improved crystallinity and reduced surface to volume ratio of Na5Yb9F32 NCs where Er3+ ions substitute in GCs sample after heat treatment will result in great enhancement of luminescent performance compared to that of PG sample. To verify this assertion, the UC and DC optical behaviors of Er3+ doped PG and GC680 were investigated. Under 980 nm near-infrared laser excitation, as presented in Fig. 3 (a), GC680 shows emission bands centered at 379 nm, 408 nm, 491 nm, 522 nm, 538 nm, and 656 nm attributing to 4G11/2 → 4I15/2, 2H9/2 → 4I15/2, 4F7/2 → 4I15/2, 2 H11/2 → 4I15/2, 4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions of Er3+, respectively. However, the peaks centered at 379 nm and the broad band around 491 nm appeared in GC680 spectra are barely visible in the PG spectra, apart from the much stronger UC luminescence of GC680 than that of PG. The integral intensity of blue, green and red in GCs enhanced about 13.4, 13.1 and 13.6 times than those of PG, respectively. The DC of GC680 is also much stronger than that of PG, as displayed in emission spectra of Fig. 3 (b) and (c) under the excitation of 377 nm and 487 nm, respectively. Moreover, under the 355nm excitation, the decay curves of luminescence in PG and GC680 at 538 nm (4S3/2→4I15/2) are also performed in Fig.3 (d). The decay curves of Er3+ in PG and GC680 can be described with two components, the fast one related to glass matrix and the slow one to Na5Yb9F32 NCs. Further heat treatment is advantageous for improving the crystallinity and reducing the surface-to-volume of Na5Yb9F32 NCs where Er3+ ions reside, which leads to a large proportion of Er3+ being incorporated into Na5Yb9F32 NCs and avoids the influence of high energy vibrations of the alumino-silicate glass matrix. Therefore, the averaged lifetime of Er3+ in GC680 is much longer than that in PG. The curves can be fitted by double exponential mode with following equation [30]:

I = A1 exp( −

t

τ1

) + A2 exp( −

t

τ2

)

(2)

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where I is the luminescence intensity; A1 and A2 are fitting parameters; t is the time, τ1 and τ2 are rapid and slow lifetimes for exponential components, respectively. Based on these parameters, the average decay times of Er3+ can be calculated by the following equation [30]:

τ=

A1τ 12 + A2τ 22 A1τ 1 + A2τ 2

(3)

The average lifetimes (τ) were determined to be 18 µs and 39 µs for PG and GC680 respectively. The decay curves of PG and GC680 samples confirmed that further heat treatment can improve the crystallinity of NCs and the luminescence of Er3+. Intriguingly, the integrated intensity ratio (Igreen/Ired) of Er3+ of GC680 decreases from 7.4 under the 487 nm excitation to 0.1 under the 377 nm excitation as calculated from Fig. 3 (c) and (b), implying different transition

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mechanisms under the excitation of 487 nm and 355 nm. To illustrate the interesting phenomenon mentioned above, the energy diagram of Yb3+ and Er3+ ions and the proposed DC mechanism of Er3+-doped Na5Yb9F32 are presented in Fig. 6. The de-excitation process under the shorter wavelength excitation will involve two main cross relaxation (CR) steps between Yb3+ and Er3+ ions: 2F7/2 (Yb3+) + 4G11/2 (Er3+) → 2F5/2 (Yb3+) + 4F9/2 (Er3+) (CR1) and 2F7/2 (Yb3+) + 2H9/2 (Er3+) → 2F5/2 (Yb3+) + 4F9/2 (Er3+) (CR2), leading to the stronger red emission from 4F9/2. The CR1 is more essential because, compared with 2H9/2 and 4F9/2 pair, the energy spacing between 4G11/2 and 4F9/2 of Er3+ is much closer to that between 2F7/2 and 2F5/2 of Yb3+. This point is also evidenced by the experimental fact that the band attributed to 4I15/2 → 2H9/2 in the excitation spectra monitoring 656 nm emission (Fig. 4 (b)) is much weaker than that corresponding to 4I15/2 → 4 G11/2 transition. The CR processes mostly occurs in NCs rather than in glass matrix since close distance between Yb3+ and Er3+ is required for their interaction. Therefore, the red emission is mainly originated from the NCs of Na5Yb9F32, though some portions of the green emission are derived from Er3+ in the glass matrix. From Fig. 4 (b), it is clearly revealed that the red emission will only be emitted when the excitation wavelength is equal or shorter than 404 nm (Er3+: 4I15/2 → 2H9/2) in the range of 250 - 500 nm. On the other hand, the green emissions can also be observed when the excitation wavelength is longer than 404 nm, as indicated in the excitation spectra monitoring 538 nm shown in Fig. 4 (a). The broad excitation band from 250 to 350 nm could be attributed to Yb2+ ions or Yb3+-O2- charge transfer state [31-34]. The narrow bands located at (355 nm, 364 nm), 377 nm, 404 nm, 440 nm, 448 nm and 486 nm are assigned to the 4I15/2 → (2G9/2, 2G7/2, 2K15/2), 4I15/2 → 4G11/2, 4I15/2 → 2H9/2, 4I15/2 → 4F3/2, 4 I15/2 → 4F5/2, and 4I15/2 → 4F7/2 of Er3+, respectively. The 4I15/2 → 4F3/2 (440 nm), 4I15/2 → 4F5/2 (448 nm), and 4I15/2 → 4F7/2 (486 nm) transitions of Er3+ are absent in Fig. 4 (b) because the large energy gap below the 4S3/2 multiplet state prevents further nonradiative transition to 4F9/2, which is responsible for the red emission. In order to clarify the UC mechanism under 980 nm excitation, the dependence of UC intensities of GC680 on the laser power are measured and presented in Fig. 5. The dependence of the UC intensity I on the incident

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pump power P usually follows I ∝ Pn, with n = 2, 3, … being the number of photons involved in the process [35]. The obtained results indicate that the green and red emissions are two-phonon process, and the blue emission is three-phonon process. The UC mechanisms are analyzed and illustrated on the basis of energy level diagram of Er3+ and Yb3+ in Fig. 6. The key UC process between Yb3+ and Er3+ is the energy transfer (ET) from the excited 2F5/2 multiplet state of Yb3+ to the 4I11/2, 4F9/2, 4F7/2, 2H9/2, and 4G9/2 multiplet sates of Er3+ ions due to the much larger absorption cross-section of Yb3+ ions than that of Er3+ ions around 980 nm. The detailed UC processes have been studied in previous works [36]. 3.4. Temperature dependence of the UC luminescence To investigate the temperature dependence of the UC luminescence behavior of GC680, the green UC emission spectra of Er3+-doped GC680 under various temperatures from 300 K to 773 K are shown in Fig. 7 (a), in which the spectra are normalized to the emission peak at 538 nm. It can be discovered that the FIR of the two emission bands in the wavelength range of 500 - 533 nm and 533 - 580 nm originate from 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions dramatically changes. The dependence of FIR on the absolute temperature is displayed in Fig. 7 (b), and the FIR increased from 0.11 to 1.34 with increasing temperature from 300 K to 773 K. As shown in Fig. 7 (a), the relative intensity of emission band originated from 2H11/2 → 4I15/2 transition increases monotonously with the raise of temperature. Due to the thermal coupling of 2H11/2 and 4S3/2, the FIR (denoted as R) of the two emission bands is related to the absolute temperature as follows [25]:

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R = A exp(−

∆E ) kBT

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SA =

dR ∆E =R dT k BT 2

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where A is a constant, ∆E is the effective energy gap between 2H11/2 and 4S3/2, kB is the Boltzmann constant, and T is the absolute temperature. As shown in Fig. 7 (b), the experimental data could be well-fitted. The effective energy gap ∆E is obtained to be 835 cm-1. This value is larger than most of those pairs that have been investigated for FIR technique. The relative sensitivity SR and absolute sensitivity SA are defined as the relative change and absolute change of the FIR value with temperature variation, which are two important parameters for temperature sensing. The SR and SA are defined in Eq. (2) and (3) as follows:

(6)

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The SR and SA values are proportional to the energy gap ∆E, so high SR and SA can be expected in the Na5Yb9F32: Er3+ glass-ceramics. Figure 7 (c) describes the theoretical fitting of relative sensitivity SR and absolute sensitivity SA of GC680 sample as a function of temperature from 300 to 773 K. In Na5Yb9F32: Er3+ glass-ceramics, the relative sensitivity value SR derived from Eq. (5) is 1201.4/T2. The maximum relative sensitivity is approximately 1.33% K-1 and this value is larger than most of other Er3+ ions-doped matrix. Moreover, the SA value increases gradually and the maximum sensitivity is approximately 2.83‰ K-1 at 601 K. These results indicate that the Na5Yb9F32: Er3+ glass-ceramics with high sensitivity, wide temperature range and better accuracy can be used as an excellent material for temperature sensor with high sensitivity.

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4. Conclusions In summary, novel transparent Er3+-doped Na5Yb9F32 GCs were successfully elaborated through melt-quenching technique. Importantly, the formation of Na5Yb9F32 NCs in glass matrix has already happened during the melt-quenching process. Due to reduced surface-to-volume ratio and more Er3+ incorporation into NCs, both of UC and DC show enhanced luminescence after heat treatment. An interesting DC phenomenon, that is the emission color would change with the excitation wavelength, was observed and studied. The FIR of the two green UC emissions peaked at 522 and 538 nm from two thermal coupling energy levels 2H11/2/4S3/2 → 4I15/2 was recorded for optical thermometry in the temperature range from 300 K to 773 K. The sensitivity of Er3+ doped Na5Yb9F32 GCs is about 1.33% K-1 at 300 K and the ∆E is 835 cm-1 in this Er3+ doped UC material. The enhanced emissions and the good temperature sensitivity suggest that the Er3+ doped Na5Yb9F32 GCs are ideal candidate for optical temperature sensing.

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Acknowledgements This work was financially supported by the National Key Basic Research and Development Program of China (Grant No. 2106YFB0701001), the National Natural Science Foundation of China (Nos. 61635012, 11574298, 11604037 and 11404321).

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References [1] S. X. Li, Q. Q. Zhu, L. Wang, D. M. Tang, Y. J. Cho, X. J. Liu, N. Hirosaki, T. Nishimura, T. Sekiguchi, Z. R. Huang, R. J. Xie, J. Mater. Chem. C 4 (35) (2016) 8197. [2] H. Suo, F. F. Hu, X. Q. Zhao, Z. Y. Zhang, T. Li, C. K. Duan, M. Yin, C. F. Guo, J. Mater. Chem. C 5 (2017) 1501. [4] C. Pagis, M. Ferbinteanu, G. Rothenberg, S. Tanase, ACS Catal. 6 (2016) 6063.

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[3] H. Zeng, X. Li, M. Sun, S Wu, H. Chen, Molecules 22(5) (2017) 753. [5] K. Ge, C. M. Zhang, W. T. Sun, H. F. Liu, Y. Jin, Z. H. Li, X. J. Liang, G. Jia, J. C. Zhang, ACS Appl. Mater. Inter. 8 (2016) 25078. [6] P. F. Smet, J. J. Joos, Nat. Mater. 16 (5) (2017) 500.

[7] L. Zhao, J. J. Cai, F. F. Hu, X. Y. Li, Z. M. Cao, X. T. Wei, Y. H. Chen, M. Yin, C. K. Duan, RSC Adv. 7 (12) (2017) 7198.

SC

[8] J. K. Cao, F. F. Hu, L. P. Chen, H. Guo, C. K. Duan, M. Yin, J. Alloys Compd. 693 (2017) 326. [9] W. J. Hu, F. F. Hu, X. Y. Li, H. W. Fang, L. Zhao, Y. H. Chen, C. K. Duan, M. Yin, RSC Adv. 6 (2016) 84610-84615. [10] X. Y. Li, G. C. Jiang, S. S. Zhou, X. T. Wei, Y. H. Chen, C. K. Duan, M. Yin, Sensor. Actuat. B-Chem. 202 (2014)

M AN U

1065.

[11] S. H. Zheng, W. B. Chen, D. Z. Tan, J. J. Zhou, Q. B. Guo, W. Jiang, C. Xu, X. F. Liu, J. R. Qiu, Nanoscale 6 (2014) 5675.

[12] S. F. León-Luis, V. Monteseguro, U. R. Rodríguez-Mendoza, I. R. Martín, D. Alonso, J. M. Cáceres, V. Lavín, J. Lumin. 179 (2016) 272.

[13] W. J. Mao, Y. M. Jia, J. Wu, Y. L. Xie, Z. Wu, J. P. Han, M. He, Funct. Mater. Lett. 9 (2016) 1650060. [14] X. T. Rao, T. Song, J. K. Gao, Y. J. Cui, Y. Yang, C. D. Wu, B. L. Chen, G. D. Qian, J. Am. Chem. Soc. 135 (2013) 15559.

TE D

[15] C. G. Lin, L. G. Li, C. Bocker, C. Rüssel, J. Am. Ceram. Soc. 99 (2016) 2878. [16] X. Y. Liu, Y. L. Wei, R. F. Wei, J. W. Yang, H. Guo, J. Am. Ceram. Soc. 96 (2013) 798. [17] Y. Gao, Y. B. Hu, D. C. Zhou, J. B. Qiu, J. Alloys Compd. 699 (2017) 303. [18] W. Xu, H. Zhao, Y. Li, L. Zheng, Z. Zhang, W. Cao, Sensor. Actuat. B-Chem. 188 (2013) 1096. [19] P. Du, L. Luo, J.S. Yu, Ceram. Int. 42 (2016) 5635.

EP

[20] Y. L. Wei, X. N. Chi, X. Y. Liu, R. F. Wei, H. Guo, J. Am. Ceram. Soc. 96 (2013) 2073. [21] Y. L. Wei, H. M. Yang, X. M. Li, L. J. Wang, H. Guo, J. Am. Ceram. Soc. 97 (2014) 2012. [22] X. Y. Li, J. K. Cao, Y. L. Wei, Z. R. Yang, H. Guo, J. Am. Ceram. Soc. 98 (2015) 3824.

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[23] D. Q. Chen, Y. L. Yu, P. Huang, F. Y. Weng, H. Lin, Y. S. Wang, Appl. Phys. Lett . 94 (2009) 041909. [24] S. Jiang, H. Guo, X. T. Wei, C. K. Duan, M. Yin, J. Lumin. 152 (2014) 195. [25] F. F. Hu, J. K. Cao, X. T. Wei, X. Y. Li, J. J. Cai, H. Guo, Y. H. Chen, C. K. Duan, M. Yin, J. Mater. Chem. C 4 (2016) 9976.

[26] J. K. Cao, W. P. Chen, L. P. Chen, X. Y. Sun, H. Guo, Ceram. Int. 42 (2016) 17834. [27] W.J. Miniscalco, J. Lightwave Technol. 9 (1991) 234. [28] C. D. Wagner, W. M. Riggs, L. E. Davis, J. F. Mouder, Handbook of X-ray photoelectron spectroscopy, G. E. Muilenberg (Ed.), Perkin-Elmer, Minnesota 1979, pp. 38-68. [29] Q. Huang, J. Yu, E. Ma, K. Kin, J. Phys. Chem. C 114 (2010) 4719.

[30] R. F. Wang, D. C. Zhou, J. B. Qiu, Y. Yang, C. Wang, J. Alloys Compd. 629 (2015) 310. [31] F. Hu, X. Wei, Y. Qin, S. Jiang, X. Li, S. Zhou, Y. Chen, C.-K. Duan, M. Yin, J. Alloys Compd. 674 (2016) 162.

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[32] L. Van Pieterson, M. Heeroma, E. De Heer, A. Meijerink, J. Lumin. 91 (2000) 177. [33] Y. Wang, X. Zhou, J. Shen, X. Zhao, B. Wu, S. Jiang, L. Li, J. Am. Ceram. Soc. 99 (2016) 115. [34] S. Kuck, M. Henke, K. Rademaker, Laser Phys. Lawrence 11 (2001) 116. [35] A. Dubey, A. K. Soni, A. Kumari, R. Dey, V. K. Rai, J. Alloys Compd. 693 (2017) 194. [36] X. Bai, H. Song, G. Pan, Y. Lei, T. Wang, X. Ren, S. Lu, B. Dong, Q. Dai, L. Fan, J. Phys. Chem. C 111 (2007)

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Captions: Fig. 1 (a) XRD patterns of PG and GC680; TEM images of samples with (c) PG and (e) GC680; (d) and (f) are HRTEM micrographs of PG and GC680 samples respectively, inset of (f) is the corresponding SAED pattern.

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Fig. 2 (a) XPS spectra of the CC680 sample in the range of 0 to 1100 ev. (b) XPS spectra of Yb 4d and Er 4d in the GC680 sample. Fig. 3 Emission spectra of Er3+-doped PG and GC680 under (a) 980 nm, (b) 377 nm, and (c) 487 nm excitation. (d) Decay curves corresponding to Er3+: 4S3/2 state in PG and GC680.

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Fig. 4 Excitation spectra by (a) monitoring the 4S3/2 emission of the Er3+ at 538 nm and (b) monitoring the 4F7/2 emission of Er3+ at 655 nm in GC680 and PG sample.

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Fig. 5 Log-Log plots of UC emission intensity versus pump power for GC680 for three emission bands. Fig. 6 Simplified energy diagram for Yb3+, Er3+ ions along with the related UC processes. Fig. 7 (a) Normalized up-conversion spectra of GC680 under the excitation of 980 nm diode laser with 13 mw/mm2 at various temperatures from 300 to 773 K. (b) R data as a function of absolute temperature for GC680 sample. (c) Relative sensitivity SR and absolute sensitivity SA of GC680 under the excitation of a 980 nm diode laser of 13 mW/mm2 in the temperature range of 300 - 775 K.

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Table 1 The experimental values determined by XPS.

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Fig. 1

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Fig. 2

Table 1

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Start BE Peak BE End BE Atomic % 292.31 284.8 281.91 56.74 180.11 170.96 162.91 0.39 211.71 186.17 180.61 2.86 690.66 685.24 681.31 20.27 1076.71 1071.86 1067.71 19.75

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Name C1s Er4d Yb4d F1s Na1s

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Fig. 3

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Fig. 4

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Fig. 5

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Fig. 6

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Fig. 7

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Novel transparent glass-ceramics Na5Yb9F32: Er3+ was successfully fabricated.
The glass-ceramics have already formed during melt-quenching process.

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The structural and morphology properties of the samples were analyzed.
Both up-conversion and down-conversion are greatly enhanced after heat treatment.

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Temperature dependent of GC680 indicates their good optical thermometry property.