共查询到20条相似文献,搜索用时 15 毫秒
1.
Guotao Xiang Menglin Yang Qing Xia Sha Jiang Yongjie Wang Xianju Zhou Li Li Li Ma Xiaojun Wang Jiahua Zhang 《Journal of the American Ceramic Society》2021,104(11):5784-5793
Light with wavelength longer than 1500 nm has great potential to afford deep bio-tissue penetration due to its extremely weak photon scattering and undetectable autofluorescence in vivo. Here, in order to satisfy the requirements for thermometry during the tumor hyperthermia process, an ultrasensitive optical thermometer operating beyond 1500 nm is developed by employing the thermally coupled Stark sublevels of Er3+: 4I13/2 → 4I15/2 transition based on fluorescence intensity ratio (FIR) technology in Yb3+ and Er3+ codoped BaY2O4. Compared with the typical upconversion (UC) material β-NaYF4: Yb3+/Er3+ and Y2O3: Yb3+/Er3+, BaY2O4: Yb3+/Er3+ shows more intense red Er3+: 4F9/2 → 4I15/2 transition and 1.5 μm near-infrared (NIR) Er3+: 4I13/2 → 4I15/2 transition induced by its larger phonon energy and higher quenching concentration of Er3+. An equivalent four-level model is proposed to investigate the temperature characteristics of the NIR emission, from which four Stark transitions are separated from the raw spectra, named α, β, γ, and δ respectively. Then, the NIR thermal sensing performance have been developed by utilizing the FIR of Iβ to Iα and Iγ to Iα. More importantly, an ultra-high sensitivity for optical thermometry has been obtained through the combination of transition β and γ, especially in the physiological temperature region. Furthermore, the detection depth of NIR light in bio-tissues is assessed by an ex vivo test, demonstrating that the maximal detection depth of NIR emission can reach to 8 mm without any influence on optical thermometry. These findings indicate that Yb3+ and Er3+ codoped BaY2O4 is a remarkable contender for optical thermometry in deep tissue with ultra-high sensitivity. 相似文献
2.
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
3.
Tomas Netolicky Lukas Strizik Ludvik Benes Klara Melanova Stanislav Slang Tomas Wagner 《Journal of the American Ceramic Society》2022,105(5):3391-3402
The nanocrystalline single-phase Er3+-doped Yb3Ga5O12 garnets have been prepared by the sol-gel combustion technique with a crystallite size of ≈30 nm. The presence of Yb3+ in garnet hosts allows their efficient excitation at the ≈977 nm wavelength. The Er3+ doping of Yb3Ga5O12 garnet host results in deep red Er3+: 4F9/2 → 4I15/2 upconversion photoluminescence (UCPL) emission. The dominance of the red UCPL emission over the green Er3+: 4F7/2/2H11/2/4S3/2 → 4I15/2 component was investigated using the measurement of the steady-state and time-dependent Er3+ and Yb3+ emission spectra in combination with the power-dependent UCPL emission intensity. The proposed upconversion mechanism is discussed in terms of the Er3+ → Yb3+ energy back transfer process as well as Yb3+(Er3+) → Er3+ energy transfer and Er3+ ↔ Er3+ cross-relaxation processes. The studied Er3+-doped Yb3Ga5O12 garnet may be utilized as a red upconversion emitting phosphor. 相似文献
4.
《Ceramics International》2022,48(16):23436-23443
Non-invasive photothermal therapy (PTT) is proposed as a powerful method for cancer treatment, in which a precise temperature monitoring is strongly recommended during the photothermal conversion process to prevent the damage of normal cells. Herein, ultra-sensitive optical thermometry with excellent resolution and outstanding light-to-heat conversion are simultaneously realized in CaSc2O4: Yb3+/Nd3+ nanorods. The temperature sensing of the nanorods is accomplished through fluorescence intensity ratio (FIR) technology based on the thermally coupled levels (TCLs) Nd3+: 4Fj (j = 7/2, 5/2, 3/2), of which the obtained absolute sensitivity is about 6.5 times larger than the optimal value of TCLs-based thermometers reported previously. Meanwhile, an intense thermal enhancement of Nd3+: 4Fj (j = 7/2, 5/2, 3/2) → 4I9/2 transition is found due to the efficiency improvement of phonon-assisted energy transfer process between Yb3+ ions and Nd3+ ions. The penetrability of the near-infrared light emitting by Nd3+ ions is determined by a simple ex vivo experiment, indicating a penetration depth of 8 mm in the biological tissues with negligible effect on FIR values. Beyond that, the nanorods show remarkable photothermal conversion capacity under the excitation of 980 nm wavelength. The properties mentioned above show enormous potentiality of the present nanorods for PTT along with a real-time temperature sensing. 相似文献
5.
Yuhang Zhang Yongze Cao Yue Zhao Xin Wang Siying Ran Long Cao Luran Zhang Baojiu Chen 《Journal of the American Ceramic Society》2021,104(1):361-368
For the development of optical temperature sensor, a series of GdTaO4 phosphors with various Er3+-doping concentrations (0, 1, 5, 10, 25, 35, 50 mol%) were synthesized by a solid-state reaction method. The monoclinic crystalline structure of the prepared samples was determined by X-ray diffraction (XRD). Under excitations of 980 and 1550 nm lasers, the multi-photon-excited green and red upconversion (UC) luminescence emissions of Er3+ were studied, and the critical quenching concentration of Er3+-doped GdTaO4 phosphor was derived to be 25 mol%. By changing the pump power of laser, it was found that the two-photon and three-photon population processes happened for the UC emissions of Er3+-doped GdTaO4 phosphors excited by 980 and 1550 nm lasers, respectively. Furthermore, based on the change of thermo-responsive green UC luminescence intensity corresponding to the 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions of Er3+ with temperature, the optical temperature sensing properties of Er3+-doped GdTaO4 phosphor were investigated under excitations of 980 and 1550 nm lasers by using the fluorescence intensity ratio (FIR) technique. It was obtained that the maximum absolute sensitivity (SA) and relative sensitivity (SR) of Er3+-doped GdTaO4 phosphors are as high as 0.0041 K−1 at 475 K and 0.0112 K−1 at 293 K, respectively. These significant results suggest that the Er3+-doped GdTaO4 phosphors are a promising candidate for optical temperature sensor. 相似文献
6.
《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
7.
Hongqiang Cui Yongze Cao Ying Li Lei Li Yuhang Zhang Guojian Li Yichao Wang Xiangping Li Baojiu Chen 《International Journal of Applied Ceramic Technology》2022,19(6):3358-3366
A series of Sr2.99-x(PO4)2:.01Er3+/xYb3+ (x = .02, .04, .06, .08, .10) phosphors in the presence of impurity Tm3+ were synthesized by high temperature solid-state method, and X-ray diffraction results show that these samples are pure R-3 m(166) space group phase. The upconversion luminescence (UCL) of Er3+ and impurity Tm3+ under 980-nm laser excitation were investigated, and the results show that the intense blue UCL of impurity Tm3+ and thermal enhancement of 2H11/2→4I15/2 of Er3+ simultaneously exist. When Er3+ doping concentration is kept at .01, both the blue UCL intensity of impurity Tm3+ and green and red UCL intensity of Er3+ reach the maximum at Yb3+ doping concentration of .08. The thermal enhancement effect of 2H11/2→4I15/2 of Er3+ was observed as high as 3.27 times from 303 to 723 K, which is because of lattice distortion and phonon-assisted transition. In addition, the optical temperature performance of Sr2.91(PO4)2:.01Er3+/.08Yb3+ sample was studied, and the maximum absolute temperature sensitivity was calculated as .00623 K−1 at 538 K. This study suggests that Sr3(PO4)2:Er3+/Yb3+ phosphors in the presence of impurity Tm3+ have a promising application prospect as optical temperature sensor at high temperature. 相似文献
8.
Microwave Sol–Gel Synthesis of CaGd2(MoO4)4:Er3+/Yb3+ Phosphors and Their Upconversion Photoluminescence Properties
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Chang Sung Lim Victor Atuchin Aleksandr Aleksandrovsky Maxim Molokeev Aleksandr Oreshonkov 《Journal of the American Ceramic Society》2015,98(10):3223-3230
CaGd2(MoO4)4:Er3+/Yb3+ phosphors with the doping concentrations of Er3+ and Yb3+ (x = Er3+ + Yb3+, Er3+ = 0.05, 0.1, 0.2, and Yb3+ = 0.2, 0.45) have been successfully synthesized by the microwave sol–gel method, and the crystal structure refinement and upconversion photoluminescence properties have been investigated. The synthesized particles, being formed after heat‐treatment at 900°C for 16 h, showed a well‐crystallized morphology. Under the excitation at 980 nm, CaGd2(MoO4)4:Er3+/Yb3+ particles exhibited strong 525 and 550‐nm emission bands in the green region and a weak 655‐nm emission band in the red region. The Raman spectrum of undoped CaGd2(MoO4)4 revealed about 15 narrow lines. The strongest band observed at 903 cm?1 was assigned to the ν1 symmetric stretching vibration of MoO4 tetrahedrons. The spectra of the samples doped with Er and Yb obtained under 514.5 nm excitation were dominated by Er3+ luminescence preventing the recording Raman spectra of these samples. Concentration quenching of the erbium luminescence at 2H11/2→4I15/2 and 4S3/2→4I15/2 transitions in the CaGd2(MoO4)4:Er3+/Yb3+ crystal structure was established to be approximately at the 10 at.% doping level. 相似文献
9.
Highly Sensitive Optical Thermometry of Yb3+‐Er3+ Codoped AgLa(MoO4)2 Green Upconversion Phosphor
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Ting Li Chongfeng Guo Shaoshuai Zhou Changkui Duan Min Yin 《Journal of the American Ceramic Society》2015,98(9):2812-2816
Er3+–Yb3+ codoped AgLa(MoO4)2 phosphors with intense green emission from 2H11/2/4S3/2 → 4I15/2 transitions and negligible red emission from 4F9/2 → 4I15/2 transition of Er3+ were synthesized by sol–gel process. Its temperature sensing performance was evaluated based on the temperature dependence of fluorescence intensity ratio (FIR) of two green emission bands in the range 300–510 K. The maximum sensitivity of AgLa(MoO4)2: 0.02Er3+/0.4Yb3+ is approximately 0.018 K?1 at 480 K, which is much higher than those of reported samples based on green emissions of Er3+. Result suggests that AgLa(MoO4)2: Er3+/Yb3+ has a great potential application in optical temperature sensors. 相似文献
10.
Wide‐range thermometry based on green up‐conversion luminescence of K3LuF6:Yb3+/Er3+ bulk oxyfluoride glass ceramics
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JiangKun Cao FangFang Hu LiPing Chen Hai Guo Changkui Duan Min Yin 《Journal of the American Ceramic Society》2017,100(5):2108-2115
Yb3+/Er3+ ions codoped bulk glass ceramics (GC) with embedded monoclinic K3LuF6 nanocrystals are reported for potential temperature‐sensing application by using the fluorescence intensity ratio method. Such GC with good transparency and enhanced up‐conversion were prepared by the simple conversional melt‐quenching method and subsequent annealing process. Optical, structural, and temperature‐sensing up‐conversion properties were characterized systematically. Optical spectroscopy analysis confirms the incorporation of Yb3+/Er3+ into the K3LuF6 crystalline lattice, resulting in enhanced up‐conversion luminescence. Compared to other Er3+‐doped typical systems, Er3+ ions in K3LuF6 GC present large energy gap (870 cm?1) and high relative sensitivity (37.6 × 10?4 K?1 at 625 K), revealing that K3LuF6:Yb3+/Er3+ GC can be excellent candidates for optical thermometers. 相似文献
11.
《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
12.
《Ceramics International》2023,49(6):9574-9583
Here we adopt trivalent lanthanide (Ln3+ = Er3+, Er3+/Ho3+, and Yb3+/Tm3+) doped Sr2LaNbO6 (SLNO) as novel upconversion luminescence (UCL) materials for achieving UCL and optical temperature sensing under 980 nm excitation. Specifically, Er3+ single doped Sr2LaNbO6 phosphors present bright high-purity green emission under the 980 nm excitation. While co-doping with the Ho3+ ions, the component of red emission from Er3+ ions increases significantly and sample show a remarkable enhancement of luminescent intensity relative to SLNO:Er3+ sample. The above-mentioned phosphors and Yb3+/Tm3+ co-doped phosphor (blue emission) successfully achieve high-purity trichromatic UCL and mixed white light output in the same host. Furthermore, the temperature sensing performance of the SLNO:Er3+/Ho3+ phosphor based on the fluorescence intensity ratio (FIR) is systematically studied for the first time. The temperature sensing based on the non-thermal coupling levels (NTCLs) exhibit higher sensitivity than that based on the thermal coupling levels (TCLs). The maximum absolute and relative sensitivity for 4F9/2/4I9/2 NTCLs reach 0.16803 K?1 at 427 K and 0.01591 K?1 at 641 K, respectively. Interestingly, NIR emission of 4I9/2 → 4I15/2 transition presents a thermal enhancement, while visible emissions show thermal quenching. These results indicate that the Ln3+ doped Sr2LaNbO6 UCL phosphors have potential applications in the fields of non-contact temperature sensors, full-color displays, and anti-counterfeiting. 相似文献
13.
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
14.
Fabrication and Upconversion Luminescent Properties of Er3+‐Doped and Er3+/Yb3+ Codoped La2O2CN2 Nanofibers
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Xiaomin Guo Wensheng Yu Xiangting Dong Jinxian Wang Qianli Ma Guixia Liu Ming Yang 《Journal of the American Ceramic Society》2015,98(4):1215-1222
La2O2CN2:Er3+and La2O2CN2:Er3+/Yb3+ upconversion (UC) luminescence nanofibers were successfully fabricated via cyanamidation of the respective relevant La2O3:Er3+ and La2O3:Er3+/Yb3+ nanofibers which were obtained by calcining the electrospun composite nanofibers. The morphologies, structures, and properties of the nanofibers are investigated. The mean diameters of La2O2CN2:Er3+ and La2O2CN2:Er3+/Yb3+ nanofibers are 179.46 ± 12.58 nm and 198.85 ± 17.07 nm, respectively. It is found that intense green and weak red emissions around 524, 542, and 658 nm corresponding to the 2H11/2→4I15/2, 4S3/2→4I15/2, and 4F9/2→4Il5/2 energy levels transitions of Er3+ ions are observed for La2O2CN2:Er3+ and La2O2CN2:Er3+/Yb3+ nanofibers under the excitation of a 980‐nm diode laser. Moreover, the emitting colors of La2O2CN2:Er3+ and La2O2CN2:Er3+/Yb3+ nanofibers are all located in the green region. The upconversion luminescent mechanism and formation mechanism of the nanofibers are also proposed. 相似文献
15.
16.
《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
17.
Yanmin Yang Chao Mi Fuyun Jiao Xianyuan Su Xiaodong Li Linlin Liu Jiao Zhang Fang Yu Yanzhou Liu Yaohua Mai 《Journal of the American Ceramic Society》2014,97(6):1769-1775
Yb3+/Er3+ codoped La2S3 upconversion (UC) phosphors have been synthesized using high‐temperature solid‐state method. Under 971‐nm excitation, the maximum luminescence power can reach 0.64 mW at the excitation power density of 16 W/cm2 and an absolute power yield of 0.36% was determined by an absolute method at the excitation power density of 3 W/cm2, and the quantum yield of La2S3:Yb3+, Er3+ (green ~0.18%, red ~0.03%, integration ~0.21) was comparable to that of NaYF4:Yb3+, Er3+ nanocrystals (integration ~0.005–0.30). Frequency upconverted emissions from two thermally coupled excited states of Er3+ were recorded in the temperature range 100–900 K. The maximum sensitivity of temperature sensing is 0.0075 K?1. As the excitation power density increases, the temperature of host materials rapidly rises and the top temperature can reach to 600 K. Given the intense UC emission, high sensitivity, as well as good photothermal stability, La2S3:Yb3+/Er3+ phosphor can become a promising composite material for photothermal ablation of cancer cells possessing the functions of temperature sensing and in vivo imaging. 相似文献
18.
In this paper, the Yb3+/Er3+ co-doped parent glass (PG) with composition (in mol%) of 30P2O5-10B2O3-38SrO-22K2O and transparent glass-ceramics (GCs) containing hexagonal Sr10(PO4)6O nanocrystals (NCs) were synthesized for the first time by melt-quenching method and subsequent heating treatment in air. Under 980 nm laser prompting, the GCs samples showed intense red and green up-conversion emissions compared to those characteristics for the PG sample. The emission intensities varied with Er3+ concentration and heat treatment conditions. Furthermore, in Yb3+/Er3+ co-doped GCs specimens, the optical thermometry was researched by means of fluorescence intensity ratio (FIR) of 4S3/2 and 2H11/2 levels. The GC sample heated at 620°C for 5 hours possessed a high relative temperature sensitivity (Sr) of 0.769% K−1 at 303 K and the maximal absolute temperature sensitivity (Sa) of 5.951 × 10−3 K−1 at 663 K, respectively. It is expected that the as-fabricated GC materials with Sr10(PO4)6O NCs are promising efficient up-conversion materials for optical temperature sensor. 相似文献
19.
《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
20.
Jiashu Sun Zhiyu Zhang Hao Suo Yuhua Chen Jinmeng Xiang Chongfeng Guo 《Ceramics International》2021,47(1):409-415
Self-monitored photo-thermal therapy (PTT) still faces huge challenge in cancer treatment, which aims to realize the real-time temperature reading during the course of optical heating. Exploiting new-type photo-thermal therapeutic agent (PTA) with thermometric function is considered to be one of effective methods to fulfill self-monitored PTT. In this work, spindle-like zircon-tetragonal (z-t) phase BiVO4:Yb3+/Er3+ up-conversion (UC) nano-particles as self-monitored PTAs were prepared through the combination of co-precipitation and hydrothermal method. Under 980 nm laser diode excitation, real-time thermometry was accomplished by monitoring thermo-responsive emission intensity ratio of Er3+ (2H11/2/4S3/2 → 4I15/2) transitions. Meanwhile, the photo-thermal conversion effect associated with UC process was trigged via the non-radiative transition channels. Considering the balance between UC emission intensity and heat generation, the optimal sample composition was determined as BiVO4:20%Yb3+/3%Er3+. Their maximum absolute sensitivity (Sa) reached 0.0125 K-1 at 460 K as the thermometer and the ability of photo-thermal conversion up to 3.32 K cm2/W as PTAs. Their potential applications in controlled subcutaneous photo-thermal treatment were estimated through ex vivo experiments. Results provided a new choice for nano-materials to realize real-time temperature feedback in the single host material (z-t BiVO4) during the course of PTT. 相似文献