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1.
《Journal of the European Ceramic Society》2017,37(15):4939-4945
Yb3+/Er3+/Tm3+ doped transparent glass ceramic containing orthorhombic YF3 nanoparticles was successfully synthesized by a melt-quenching method. After glass crystallization, tremendously enhanced (about 5000 times) upconversion luminescence, obvious Start-splitting of emission bands as well as long upconversion lifetimes of Er3+/Tm3+ confirmed the incorporation of lanthanide activators into precipitated YF3 crystalline environment with low phonon energy. Furthermore, temperature-dependent upconversion luminescence behaviors of glass ceramic were systematically investigated to explore its possible application as optical thermometric medium. Impressively, both fluorescence intensity ratio of Er3+: 2H11/2 → 4I15/2 transition to Er3+: 4S3/2 → 4I15/2 one and fluorescence intensity ratio of Tm3+: 3F2,3 → 3H6 transition to the combined Tm3+: 1G4 → 3F4/Er3+: 4F9/2 → 4I15/2 ones were demonstrated to be applicable as temperature probes, enabling dual-modal temperature sensing. Finally, the thermal effect induced by the irradiation of 980 nm laser was found to be negligible in the glass ceramic sample, being beneficial to gain intense and precise probing signal and detect temperature accurately. 相似文献
2.
In this study, Sm3+/Tb3+-co-doped NaGd(MoO4)2 phosphors were prepared via the hydrothermal method, with sodium citrate used as a chelator. X-ray diffraction confirmed the structure of the samples, and the test outcomes showed that the phosphors exhibited a body-centered tetragonal structure. Field-emission scanning electron microscopy results showed that the specimen morphology changed with the change in the Cit3?/Re3+ molar ratio. Moreover, the measured temperature-dependent emission spectra showed that Sm3+ and Tb3+ had different quenching trends; thus, the fluorescence intensity ratio can be used to represent temperature. In addition, the outcome of this experiment revealed that the temperature-sensing sensitivity of the phosphors gradually increased with the increasing Cit3?/Re3+ ratio, and the highest sensitivity value was 0.346 K?1 (at 503 K, Cit3?/Re3+ = 2). When the temperature was 298–369 K, the temperature-sensing relative sensitivity increased with increasing Cit3?/Re3+, but in the range 374–503 K, the relative sensitivity decreased with increasing Cit3?/Re3+. The highest relative sensitivity value of the sample was 2.7% K?1 (404 K, Cit3?/Re3+ = 0). Additionally, the Commission International del’Eclairage chromaticity coordinates displayed that the luminous colors of Sm3+/Tb3+-co-doped specimens continuously changed from green to red as the temperature changed. 相似文献
3.
《Ceramics International》2022,48(3):3051-3058
Contactless optical thermometers have attracted extensive attentions for applications in scientific research and technological fields due to their apparent advantages. Herein, a novel sequence of Ba3-xSrxLu4O9 (B3-xSxLO):Er3+/Yb3+ phosphors were successfully prepared to investigate the temperature sensing property. By establishing energy transfer from Yb3+ to Er3+ and regulating the local lattice environment, up-conversion luminescence of Er3+ is dramatically improved when excited by 980 nm laser. This can effectively promote signal-noise ratio and reduce the errors in temperature detection. Furthermore, a multi-mode optical thermometry, which includes the fluorescence intensity ratio (FIR) from two thermally coupled levels of 2H11/2/4S3/2, FIR based on non-thermally coupled system of 2H11/2/4F9/2 and fluorescence lifetime of 4S3/2 state of Er3+, was explored systematically. The fabricated samples exhibit the superior temperature measurement performances containing wide temperature-sensing range, superior signal discriminability, high sensitivity and favorable repeatability, indicative of the enormous utilization prospects of B3-xSxLO:Er3+/Yb3+ for thermometry. 相似文献
4.
Dongyu Li Weijiang Xu Zhen Huang Xiao Jin Bing Xu Zhenghe Zhang Tingting Zhang Deng Wang Xuping Liu Hao Suo Qinghua Li 《Journal of the American Ceramic Society》2023,106(1):438-447
The effects of site symmetric distortion induced by the phase transition on up-conversion emission and thermal sensing performance of Gd2(MoO4)3:Yb3+/Er3+ (GMO) crystals were elaborately studied by minimizing interference from many factors. Monoclinic GMO showed a much stronger fluorescence intensity and larger fluorescence intensity ratio under the irradiation of 980 nm laser in comparison to the orthorhombic counterpart. These remarkable up-conversion properties stemmed from the low site symmetry with large site symmetric distortion in monoclinic GMO. Moreover, the thermal sensing property of the samples was assessed based on the fluorescence intensity ratio technique, where monoclinic GMO exhibited much higher maximum absolute sensitivity (Sa = 0.0257 K−1 at 510 K) due to the site symmetric distortion, which was further explained by the Judd–Ofelt theory and polarizability of the chemical bond volume model. Results opened an efficient avenue for achieving highly sensitive thermometry in many daily scenarios via finely tailoring the local site symmetry. 相似文献
5.
《Ceramics International》2019,45(14):16911-16917
This work presents the structural, morphological and luminescent, properties of SrGe4O9 (SGO):Er3+,Yb3+ phosphors. These phosphors were synthesized by simple combustion synthesis and subsequently annealed at 1100 °C. The XRD patterns revealed that all the SGO samples doped with Yb3+ concentrations from 2 to 10 at.% presented a trigonal pure phase (the Er3+ concentration was fixed to 1 at.%). The morphology of the SGO samples was analyzed by scanning electron microscopy and found that they are formed by microparticles with irregular shapes and average sizes in the range of 0.2 μm–3 μm. The luminescence measurements of the SGO:Er3+,Yb3+ samples showed the presence of two main emission bands at 551 nm (green) and at 662 nm (red) under excitation at 980 nm, which are associated to Er3+ transitions. For Yb concentration of 2 and 3 at.% the green band dominated, but the red band became more intense for Yb concentrations above 5 at.%. As result, the CIE coordinate changed from the green to the yellow region. The increase for the Yb content from 2 to 10 at.% also enhanced of the NIR emission of Er3+ ≈5 times and the maximum upconversion emission was observed for 8% of Yb concentration. Further, the surface of the SGO samples was analyzed by the FTIR technique in order to find OH groups which are common luminescent quenching centers, but these groups were not detected on the samples. Since the SGO samples presented tunable emission, absence of OH groups on their surface and stable crystalline structure for high Yb dopant concentrations, they could be good candidates as phosphors for solid state lighting or displays applications. 相似文献
6.
《Ceramics International》2019,45(10):13235-13241
Yb3+:Ho3+ co-doped Gd2O3 nanoparticles were successfully synthesized by pulsed laser ablation in water under different laser energy. The phase structure, morphology, crystallization and upconversion photoluminescence properties of obtained samples were investigated using X-Ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and photoluminescence spectra. The mechanism of the upconversion process was discussed based on the energy level diagram and power dependent upconversion emission. Upconversion mechanisms and thermal effects caused by absorption of excitation laser were discussed. Temperature dependent green and red emissions of Yb3+:Ho3+ co-doped Gd2O3 nanoparticles under the excitation of 980 nm were investigated in the low temperature range of 130 K–280 K. Non-radiative decay rate theory was used to explain the difference of quenching rates of green and red emissions. A further study on temperature sensing properties based on fluorescence intensity ratio (FIR) of green and red emissions was carried out. The FIR as a function of temperature can be well fitted by the model based on the thermal quenching theory. The relative sensitivity reaches its maximum value of 0.804% K−1 at 216 K. 相似文献
7.
《Ceramics International》2022,48(3):3860-3868
The photoluminescence and temperature sensitivities of Ca3Y2Si3O12:Pr3+ thermo-phosphors with silico-carnotite structure obtained by solid state reaction method were investigated. Pr3+ ions were accommodated in the A sites having coordination number of 9 in AB2C2(SiO4)3 to replace Y3+ ions. The typical sample consisted of microcrystals with an irregular structure and the surface of particles was smooth, which could enhance the luminescence due to reducing the scattering and non-radiation produced by rough surfaces. The band gap value of typical sample was about 4.01 eV. Dipole-dipole interaction could account for concentration quenching. The two thermometry strategies including normalized intensities from 3P0→3H4 transition and Fluorescence intensity ration (FIR) of 3P0→3H4/3P1→3H5 transitions were employed for temperature sensing in 298–573 K. The results revealed that Ca3Y2Si3O12:Pr3+ thermo-phosphors had good temperature sensitivity performance with maximum Sr of 0.59% K?1@573 K and 0.762% K?1@298 K in the above two methods, respectively. Hence, Ca3Y2Si3O12:Pr3+ would be a promising candidate in the field of optical thermometry. 相似文献
8.
《Ceramics International》2020,46(11):18614-18622
Studies on lanthanide ions doped upconversion nanomaterials are increasing exponentially due to their widespread applications in various fields such as diagnosis, therapy, bio-imaging, anti-counterfeiting, photocatalysis, solar cells and sensors, etc. Here, we are reporting upconversion luminescence properties of NaBi(MoO4)2:Ln3+, Yb3+ (Ln = Er, Ho) nanomaterials synthesized at room temperature by simple co-precipitation method. Diffraction and spectroscopic studies revealed that these nanomaterials are effectively doped with Ln3+ ions in the scheelite lattice. DR UV–vis spectra of these materials exhibit two broad bands in the range of 200–350 nm correspond to MoO42− charge transfer, s-p transition of Bi3+ ions and sharp peaks due to f-f transition of Ln3+ ions. Upconversion luminescence properties of these nanomaterials are investigated under 980 nm excitation. Doping concentration of Er3+ and Yb3+ ions is optimized to obtain best upconversion photoluminescence in NaBi(MoO4)2 nanomaterials and is found to be 5, 10 mol % for Er3+, Yb3+, respectively. NaBi(MoO4)2 nanomaterials co-doped with Er3+, Yb3+ exhibit strong green upconversion luminescence, whereas Ho3+, Yb3+ co-doped materials show strong red emission. Power dependent photoluminescence studies demonstrate that emission intensity increases with increasing pump power. Fluorescence intensity ratio (FIR) and population redistribution ability (PRA) of 2H11/2 → 4I15/2, 4S3/2 → 4I15/2 transitions of Er3+ increases with increasing the Yb3+ concentration. Also, these values increase linearly with increasing the pump power up to 2 W. It reveal that these thermally coupled energy levels are effectively redistributed in co-doped samples due to local heating caused by Yb3+. 相似文献
9.
Abstract
Powders of Y2O3 co-doped with Yb3+ and Er3+ composed of well-crystallized nanoparticles (30 to 50 nm in diameter) with no adsorbed ligand species on their surface are prepared by polymer complex solution method. These powders exhibit up-conversion emission upon 978-nm excitation with a color that can be tuned from green to red by changing the Yb3+/Er3+ concentration ratio. The mechanism underlying up-conversion color changes is presented along with material structural and optical properties.PACS
42.70.-a, 78.55.Hx, 78.60.-b 相似文献10.
《Ceramics International》2023,49(8):11829-11836
Fluorescence temperature measurement technology has set off another upsurge in non-contact temperature measurement, but still suffers from the large error for single-mode thermometry. Herein, in a broad temperature range of 93–633 K, a dual-mode modulation thermometry based on up-conversion phosphor of GaNbO4:Yb3+/Er3+ is realized with the maximum relative sensitivity (Sr) of 11.7% K−1 (93 K) and 13.1% K−1 (123 K), respectively. GaNbO4:Yb3+/Er3+ phosphors were synthesized by high temperature solid-state method. The structure, surface morphology and the optical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL). The fluorescence intensity ratio (FIR) readout method based on Er3+ thermal-coupled energy level (TCL) and non-thermal-coupled energy level (NTCL) was used to achieve the dual-mode temperature measurement with high temperature resolution and good repeatability in GaNbO4:5 mol% Yb3+ and 5 mol% Er3+ phosphors. All the results show that GaNbO4:Yb3+/Er3+ phosphors have great application potential in high sensitivity broadband thermometry. 相似文献
11.
《Ceramics International》2023,49(19):31618-31626
In recent years, lanthanide doped materials have been extensively studied in the field of fluorescence temperature sensing due to their abundant emission levels and sensitive thermal response. Temperature sensing based on fluorescence intensity ratio (FIR) of upconversion nanoparticles has the advantages of fast temperature response, non-aggressiveness, and high spatial resolution. However, the most reported FIR sensing has limited sensitivity, probably due to the use of thermal coupling levels. Herein, we report a novel FIR temperature measurement based on non-thermal coupling levels of NaGdF4:Yb3+/Er3+@NaGdF4@NaGdF4:Yb3+/Tm3+ core-shell-shell nanostructure, which has high sensitivity and robustness simultaneously. The relative sensitivity based on I801/I654 and I801/I841 of Tm3+ to Er3+ can reach up to 4.56 (303 K) and 3.82% K−1 (313 K), respectively. Between them, FIR of I801/I841 is independent of excitation power and time. These results show the great potential of FIR based on non-thermal coupling levels in high-sensitive and robust temperature sensors. 相似文献
12.
《Ceramics International》2020,46(14):22164-22170
For a long time, rare-earth ion-doped phosphors have been widely used in temperature sensing because of their excellent light-emitting properties. However, most of the rare earth elements are relatively rare and expensive, so the transition group elements that are economical and easy to obtain have been favored by researchers. This paper presents a new type of phosphor doped with rare earth ion and transition metal for optical temperature measurement. In recent years, Mn4+-doped phosphors have attracted wide attention because of their strong deep red light-emitting properties. La2LiSbO6 provides a good host environment for Mn4+ and Eu3+ due to its unique crystal structure. In this paper, a series of La2LiSbO6 phosphors singly doped with Mn4+ and Eu3+, and co-doped with Eu3+/Mn4+ were synthesized. The crystal phases and optical properties of these materials were characterized and analyzed in detail. We specifically studied the temperature dependence of the fluorescence intensity of the optimized La2LiSbO6: Eu3+, Mn4+ phosphors at 303K–523K. The experimental results prove that the thermal responses of Mn4+ and Eu3+ are different. With increasing temperature, the thermal quenching of the Mn4+ fluorescence intensity is much faster than that of Eu3+, so the temperature characteristics can be explored by the fluorescence intensity ratio (FIR) of Eu3+ to Mn4+. At 523 K, its maximum relative sensitivity and maximum absolute sensitivity can reach 0.891% K−1 and 0.000264 K-1, respectively. Our experimental analysis shows that La2LiSbO6:Eu3+/Mn4+ phosphors have relatively high temperature sensitivity and have potential application prospects in the field of high temperature sensing. 相似文献
13.
Teng Zheng Laihui Luo Peng Du Anmeng Deng Weiping Li 《Journal of the European Ceramic Society》2018,38(2):575-583
The (0.98-x)(0.6Pb(Mg1/3Nb1/3)O3-0.4PbTiO3)-xPb(Yb1/3Nb1/3)O3-0.02Pb(Er1/2Nb1/2)O3 ((0.98-x)(PMN-PT)-xPYN:Er3+) ceramics were prepared through a solid-state reaction method. The phase structure, piezoelectric response, ferroelectric performance and upconversion emission of the ceramics were systematically investigated. The phase structure, the electrical and optical properties are strongly related to the content of PYN. The optimized piezoelectric response and upconversion emissions of the ceramics were achieved near x = 0.12, which locates in the morphotropic phase boundary (MPB) composition. Furthermore, the temperature sensing behaviors of the resultant compounds based on the thermally coupled levels of 2H11/2 and 4S3/2 of Er3+ ions in the temperature range of 133–573 K were studied by utilizing the fluorescence intensity ratio technique. Additionally, the thermal effect, which is induced by the laser pump power, of the studied ceramics is also investigated and the produced temperature is enhanced from 268 to 348 K with the pump power rising from 109 to 607 mW. 相似文献
14.
《Ceramics International》2022,48(2):2230-2240
A series of BaBi2-xNb2ErxO9 ceramic compositions with different Er3+ concentration (x = 0.0–8 mol %) is synthesized by a conventional solid-state reaction method. The upconversion (UC) light emission under 980 nm excitation with different pump powers and luminescence-based temperature sensing ability of BaBi2-xNb2ErxO9 composition have been examined. The formation of a Bi-layered perovskite phase of BaBi2Nb2O9 is confirmed having an orthorhombic geometry and Fmmm space group. Shifts in the Raman modes indicate reduced interaction of Bi3+ ions with NbO6 octahedron leading to relaxation of structural distortion with increasing Er3+ content. The maximum value for remnant polarization and coercive field of doped BaBi2-xNb2ErxO9 ceramic for (x = 0.08) Erbium concentration comes out to be 2.9524 μC/cm2 and 49.8980 kV/cm. For an optimum content of x = 0.04, two strong UC green emission bands were observed at 549 nm via 4S3/2 → 4I15/2 transition and 527 nm via 2H11/2 → 4I15/2 transitions, and a weak red emission appears at 657 nm attributed to the 4F9/2 → 4I15/2 transition. Pump power dependence suggests that UC emission is a two-photon mechanism for red and green emission bands. Temperature sensing evaluated by the change in the fluorescence intensity ratio (I527/I549) indicates the highest sensitivity to be 0.00996 K?1 at 483 K for an optimum concentration of Er3+ at x = 0.04 in BaBi2-xNb2ErxO9 composition and is useful for non-contact optical thermometry. 相似文献
15.
Guotao Xiang Xiaotong Liu Wen Liu Bin Wang Zhen Liu Sha Jiang Xianju Zhou Li Li Ye Jin Jiahua Zhang 《Journal of the American Ceramic Society》2020,103(4):2540-2547
A conventional high temperature solid state method was utilized to prepare CaO-Y2O3, which is a potential candidate for manufacturing crucible material to melt titanium and titanium alloys with low cost. Meanwhile, Yb3+ ions and Er3+ ions were selected as the sensitizers and activators respectively to dope into CaO-Y2O3, aimed at providing real-time optical thermometry during the preparation process of titanium alloys realized using fluorescence intensity ratio (FIR) technology. The results reveal that a high measurement precision can be acquired by using the Stark sublevels of Er3+ 4F9/2 to measure the temperature with a maximum absolute error of only about 3 K. In addition, by analyzing the dependence of 4I13/2 → 4I15/2 transition on pump power of 980 nm excitation wavelength, it was found that the laser-induced thermal effect has almost no influence on the temperature measurement conducted by using the FIR of the Stark sublevels of Er3+ 4I13/2, which means that a high excitation pump power can be used to obtain strong NIR emission and good signal-to-noise ratio for optical thermometry without the influence of the laser-induced thermal effect. All the results reveal that CaO-Y2O3: Yb3+/Er3+ is an excellent temperature sensing material with high measurement precision. 相似文献
16.
K. Naveen Kumar L. Vijayalakshmi Hyeongyu Bae Kang Taek Lee Pyung Hwang Jungwook Choi 《Ceramics International》2021,47(4):4563-4571
Yb3+/Er3+codoped La10W22O81 (LWO) nanophosphor rods have been successfully synthesized by a facile hydrothermal assisted solid state reaction method, and their upconversion photoluminescence properties were systematically studied. X-ray diffraction patterns revealed that the nanophosphors have an orthorhombic structure with space group Pbcn (60). A microflowers-like morphology with irregular hexagonal nanorods was observed using field emission scanning electron microscopy for the Yb3+(2 mol%)/Er3+(2 mol%):LWO nanophosphor. The shape and size of the nanophosphor and the elements along with their ionic states in the material were confirmed by TEM and XPS studies, respectively. A green upconversion emission was observed in the Er3+: LWO nanophosphors under 980 nm laser excitation. A significant improvement in upconversion emission has been observed in the Er3+: LWO nanophosphors by increasing the Er3+ ion concentration. A decrease in the upconversion emission occurred due to concentration quenching when the doping concentration of Er3+ ions was greater than 2 mol%. An optimized Er3+(2 mol%): LWO nanophosphor exhibited a strong near infrared emission at 1.53 μm by 980 nm excitation. The green upconversion emission of Er3+(2 mol%): LWO was remarkably enhanced by co-doping with Yb3+ ions under 980 nm excitation because of energy transfer from Yb3+ to Er3+. The naked eye observed this upconversion emission when co-doping with 2 mol% Yb3+. In order to obtain the high upconversion green emission, the optimized sensitizer concentration of Yb3+ ions was found to be 2 mol%. The upconversion emission trends were studied as a function of stimulating laser power for an optimized sample. Moreover, the NIR emission intensity has also been enhanced by co-doping with Yb3+ ions due to energy transfer from Yb3+ to Er3+. The energy transfer dynamics were systematically elucidated by energy level scheme. Colorimetric coordinates were determined for Er3+ and Yb3+/Er3+: LWO nanophosphors. The energy transfer mechanism was well explained and substantiated by several fluorescence dynamics of upconversion emission spectra and CIE coordinates. The results demonstrated that the co-doped Yb3+(2 mol%)/Er3+(2 mol%): LWO nanophosphor material is found to be a suitable candidate for the novel upconversion photonic devices. 相似文献
17.
《Ceramics International》2016,42(5):5635-5641
A series of Yb3+ ions sensitized NaY(WO4)2:Er3+ phosphors were synthesized through a solid-sate reaction method. The X-ray diffraction (XRD), upconversion (UC) emission and cathodoluminescence (CL) measurments were applied to characterize the as-prepared samples. Under the excitation of 980 nm light, bright green UC emissions corresponding to (2H11/2,4S3/2)→4I15/2 transitions of Er3+ ions were observed and the UC emission intensities showed an upward trend with increasing the Yb3+ ion concentration, achieving its optimum value at 25 mol%. Furthermore, the temperature sensing behavior based on the thermally coupled levels (2H11/2,4S3/2) of Er3+ ions was analyzed by a fluorescence intensity ratio technique. It was found that the obtained samples can be operated in a wide temperature range of 133–773 K with a maximum sensitivity of approximately 0.0112 K−1 at 515 K. Ultimately, strong CL properties were observed in NaY(WO4)2:0.01Er3+/0.25Yb3+ phosphors and the CL emission intensity increased gradually with the increment of accelerating voltage and filament current. 相似文献
18.
Splitting upconversion emission and phonon‐assisted population inversion of Ba2Y(BO3)2Cl:Yb3+, Er3+ phosphor
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Anjun Huang Zhengwen Yang Chengye Yu Jianbei Qiu Zhiguo Song 《Journal of the American Ceramic Society》2017,100(11):4994-4998
Upconversion (UC) peak of 4S3/2→4I15/2 transition of Er3+ is close to that of 2H11/2→4I15/2 transition. The UC emission splitting of Er3+ caused by coordination fields of host results in that it is difficult to confirm which transitions (4S3/2→4I15/2 or 2H11/2→4I15/2) are responsible for the splitting UC emission peaks. In this work, the UC luminescence peaks located at 524, 540, 551, 565, 662, 677, and 683 nm were observed in the Ba2Y(BO3)2Cl:Yb3+, Er3+ phosphor upon the 980 nm excitation. The 524 and 540 nm UC emissions intensity were increased, while the 551 and 565 nm UC emissions intensity were decreased with the temperature increasing from 323 to 573 K, which is attributed to the phonon‐assisted population inversion from the 4S3/2 to 2H11/2 level. The temperature dependence of UC emission spectra demonstrated that the 524 and 540 nm UC emissions are from 2H11/2→4I15/2 transition, and 551 and 565 nm UC emissions are from the 4S3/2→4I15/2 transition. Temperature sensing property was characterized by the UC intensity ratio of the 2H11/2→4I15/2 transition to 4S3/2→4I15/2 transition. The Ba2Y(BO3)2Cl:Yb3+,Er3+ phosphor has potential application as the non‐contact temperature sensor. 相似文献
19.
Xiaohui Feng Le Wang Ran Wei Ziyan Wang 《Journal of the American Ceramic Society》2020,103(2):1046-1056
Non-contact temperature sensors based on the fluorescence intensity ratio (FIR) have been widely investigated owing to their high sensitivity and reliable real-time monitoring. Herein, the SiO2-coated LiY(MoO4)2@SiO2:Er3+,Yb3+ phosphor was investigated as an optical thermometry material, which was synthesized using the conventional solid state reaction and coated by a facile wet chemical route. The effect of surface modification on FIR was systematically characterized by structural analyses and spectral measurements and the temperature-dependent up-conversion FIR was investigated from 303 to 603 K under a 980 nm laser excitation. The results showed that the FIR value was thermally stable and the SiO2 coating led to a higher FIR sensitivity as well as a higher saturation threshold. This work would pave a way to design interesting optical thermometry materials in up-conversion phosphors with better properties. 相似文献
20.
《Ceramics International》2016,42(5):6094-6099
Dy3+/Tb3+ codoped CaMoO4 phosphors were synthesized by a simple sol–gel method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence spectroscopy. The energy transfer process of Dy3+→Tb3+ was confirmed by excitation and emission spectra and luminescence decay curves, and the energy transfer efficiency was also estimated. The results verified that the efficient emission of Tb3+ was sensitized by Dy3+ under the excitation of 354 nm, realizing tunable emission in CaMoO4 phosphors. Furthermore, optical thermometry was achieved by the fluorescence intensity ratio between Tb3+: 5D4→7F5 (~546 nm) and Dy3+: 4F9/2→6H13/2 (~575 nm). It is expected that the investigated CaMoO4 nanograins doped with Dy3+/Tb3+ have prospective applications in display technology and optical thermometry. 相似文献