JOURNAL OF LUMINESCENCE
·
2019
·
IF 2.961
Lu Liu,Dongyang Tang,Li Xu,Fahim Khan,Isam Ud Din,Zhao Wang,Pengfei Li,Hanyang Li,Enming Zhao,Yang Zhang
Various concentrations of Ho 3+ and Nd 3+ codoped NaYF 4 nanorods were successfully synthesized. On the basis of the upconversion spectra under 808 nm excitation, the luminescence mechanisms were discussed in detail. The ratio of red to green intensity evidently increases with increasing the Nd 3+ content due to the stronger interactions between Ho 3+ and Nd 3+ , which enhance the red emission and suppress the green one. In addition, we found that the red emission is more sensitive to the ambient temperature as compared to the green one, thus validating the thermal sensing by applying the ratiometric method by using these two emission bands. Relatively high sensing sensitivity of 0.9% was obtained, evidencing the great potential of the presented optical thermometer.
研究领域:
材料科学
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光学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHYSICS D-APPLIED PHYSICS
·
2018
·Vol. 51
·期 35
·355301
·
IF 2.373
Tao Pang,Ronghua Jian,Jianping Xie,Wenhui Lu
The cubic phase KY3F10:15%Yb3+,1%Ho3+ up-converting nanocrystals are prepared by a simple hydrothermal method. Under 980 nm excitation, strong green and red emissions are produced at the same time. According to a set of steady state rate equations and the power dependence of up-conversion luminescence, it is confirmed that two-step energy transfer from Yb3+ to Ho3+dominates the population of green emission level, while the multi-phonon decay of 5S2/5F4 to 5F5 and promotion from 5I7 to 5F5 are responsible for the red emission. Long-term laser irradiation leads to significant thermal effects. Based on the ratiometric luminescence temperature sensing behavior, the light to heat conversion ability is evaluated. This multi-functional nanocrystal is potentially applicable as the nano-heater for photo-thermal therapy of tumors.
研究领域:
材料科学
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医学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2020
·Vol. 104
·期 4
·1785-1796
·
IF 3.502
Jianqiang Bi,Tong Wei,Linghui Shen,Fengming Yang,Chuanzhen Zhao,Mingchao Wang,Qiqian Yang,Yuxuan Lin
Upconversion (UC) luminescence modulation is quite important in controlling and processing light for active components of light sources, photoswitches, optical memories, and optical sensing devices. In this work, we reported one kind of novel phosphor, Ho 3+ /Yb 3+ -doped SrBi 4 Ti 4 O 15 ceramics, which displayed both strong UC luminescence and obvious photochromic (PC) reaction. The UC luminescence, PC effect, and the modulation of UC performance based on PC behavior were investigated in detail. By alternating visible light irradiation and thermal stimulus, the UC luminescence could be reversibly regulated. Meanwhile, the modulation was unveiled to tightly rely on the irradiation time and thermal treatment processes. Excellent reproducibility was also achieved. In addition, as an alternative method to thermal treatment, the manipulation of luminescence by electric field was also explored. Finally, the mechanism related to the UC luminescence manipulation was illustrated. The results indicate that these samples could be potentially utilized in optical data storage and anti-counterfeiting security fields.
研究领域:
材料科学
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光学
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2025
·
IF 2.5
Wang Fangyu,Wen Yijie,Guo Xin,Zhang Xuanhao,Hu Shuai,Yuan Maohui,Han Kai
Upconversion nanomaterials have been extensively applied in many fields owing to their unique optical and electronic properties. In this work, β-NaYF 4 :Yb 3+ /Ho 3+ microcrystals were synthesized by an improved hydrothermal method. The morphology and the composition of the prepared microcrystals were experimentally investigated in detail by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Under the excitation of a 980 nm continuous-wave (CW) laser, the green (541 nm) and red (644 nm) upconversion luminescence (UCL) of Ho 3+ through the energy transfer upconversion processes assisted by the Yb 3+ ions were experimentally studied at the single-particle level. With the gradual increase of excitation intensity in the highly doped Yb 3+ microcrystals, the red UCL was enhanced significantly more than the green UCL and was dominant, resulting in the UCL color finally tuning to pure red. Comparatively, for the lightly doped Yb 3+ microcrystals, the green UCL exhibited a relatively similar increase to the red UCL. The populations of the Yb 3+ and Ho 3+ ions and transitions of the UCL were systematically demonstrated through calculation of the energy levels. Notably, a new UCL at 580 nm was observed, which was ascribed to the transition of 5 F 1 , 5 G 6 → 5 I 7 .
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2024
·Vol. 130
·期 6
·1-10
·
IF 2.5
He Yu,Li Xin,Guo Yangyang,Mao Huibing,Chen Ye,Wang Jiqing
The ZnS: Ho 3+ , Yb 3+ , Mn 2+ nanomaterials fabricated by the co-precipitation method have the zinc-blende structure with the crystallite size about 90 ∼ 100 nm. The X-ray diffraction (XRD), the scanning electron microscope (SEM) and the transmission electron microscope (TEM) characterizations confirm that the doping of the Mn 2+ has less effect on the structure of the ZnS: Ho 3+ , Yb 3+ , Mn 2+ nanomaterials. With the excitation of a 978 nm laser, the upconversion (UC) emissions of the ZnS: Ho 3+ , Yb 3+ , Mn 2+ nanomaterials include two emission bands located at 551 and 664 nm, which correspond to the transitions 5 F 4 ( 5 S 2 )→ 5 I 8 and 5 F 5 → 5 I 8 of the Ho 3+ ions. The UC emission characterization confirms that the UC emission of the ZnS: Ho 3+ , Yb 3+ nanomaterials can be modulated by the doping of the Mn 2+ ions, the increase of the incident laser power and the change of the laser pulse-width. The red emission of the ZnS: Ho 3+ , Yb 3+ nanomaterials particle will increase significantly with the incorporation of the Mn 2+ ions. The incident laser power and the laser pulse-width also can modulate the intensity ratio G / R of the green to the red. With the increase of the incident laser power, the emission intensity ratio G / R will also increase. With the increase of laser pulse-width from 0.2 to 0.8 ms, the above intensity ratio G/R will decrease significantly. The modulation between the green and red emission is due to the energy transfer from the 5 F 4 ( 5 S 2 ) state to the 5 F 5 state of the Ho 3+ ions through the state 4 T 1 of the Mn 2+ ions.
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 42
·15539-15548
·
IF 4
Shanshan Zhao,Benchun Li,Tiantian Shen,Fang Fang,Songlin Zhuang,Dawei Zhang,Dechao Yu
Development of novel ultraviolet (UV) upconversion materials has been emerging as a hot research topic for application in tunable UV lasers, photocatalysis, sterilization, tagging, and most recently luminescence thermometry. We readily synthesized a series of Ho3+/Gd3+ co-doped LiYO2 upconversion phosphors by a traditional high-temperature reaction. Under excitation from a blue ∼445 nm laser, LiYO2:Ho3+,Gd3+ polycrystalline powders yield intense sharp ultraviolet B (UVB) upconversion luminescence from Gd3+ 6Pj (j = 7/2, 5/2, 3/2) excited states. By means of steady and dynamic photoluminescence spectra, we systematically investigated the involved two-photon absorption upconversion as well as the accompanying energy transfer processes between Ho3+ and Gd3+ ions in the LiYO2 host lattice. Interestingly, the distinguishable UVB luminescence constituents from Gd3+ 6Pj excited states exhibit sensitive temperature dependence in a 353–673 K range. Shedding light on thermal equilibria between Gd3+ 6Pj UV-emitting levels, their luminescence intensity ratios follow Boltzmann statistics for the application of new luminescence thermometry. For the scheme of 6P7/2–6P3/2 thermally coupled levels, it works over a temperature range of 373–673 K with a maximum relative sensitivity (Sr) of about 1.07% K−1 at 373 K, and its 6P7/2–6P5/2 counterpart works over 353–533 K with a maximum Sr of about 0.83% K−1 at 353 K. Overall, our study provides a new pathway to develop UV upconversion materials, and promotes the application of Gd3+-related UV luminescence constituents in sensitive temperature sensing over a wide temperature range.
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2025
·
IF 4.7
Wenzhi Su,Mengyu Zhang,Chuancheng Zhang,Yong Zou,Wenpeng Liu,Shoujun Ding
Upconversion (UC) fluorescence intensity ratio (FIR) technology has emerged as a promising approach for optical thermometry due to its ability to provide non-contact, high-precision temperature measurements. Unlike conventional UC phosphor-based systems, single-crystal UC materials offer enhanced responsiveness and sensitivity for thermal detection, thanks to their structural stability and superior thermal conductivity. In this study, we successfully synthesized an Yb 3+ , Ho 3 ⁺:NaBi(MoO 4 ) 2 (NBM) single crystal with exceptional optical quality using the Czochralski (Cz) growth technique. Comprehensive structural characterization was carried out using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). The results confirmed that Yb 3+ , Ho 3+ :NBM crystallizes in a tetragonal structure with the space group I4 1 /a. The emission of different visible light colors under various excitation wavelengths was found to be due to the multiphonon relaxation process. Systematic analysis of power-dependent up-conversion emission spectra conclusively showed that the green and red up-conversion emissions arise from two-photon excitation processes. Moreover, temperature-dependent spectral evolution in the range of 300–500 K was quantitatively analyzed, allowing the calculation of both absolute sensitivity ( S ₐ) and relative sensitivity ( S ᵣ) parameters to evaluate the material's optical thermometric performance. These findings highlight the promising potential of Yb 3+ , Ho 3+ :NBM single crystal for developing high-performance optical thermometry devices.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2023
·
IF 3.6
Yanting Liu,Yanzhu Wang,Lili Meng,Qi Pang,Hua Yao,Qian Chen,Sidi Ye,Yanting Li,Minyi Zheng
Herein, we successfully obtained Ho 3+ and Ag + -codoped Cs 2 NaBiCl 6 halide double perovskites (DPs) via a hydrothermal method , which exhibit orange-red broadband self-trapped excitons (STE) emission and visible (Vis) and near-infrared (NIR) narrow band emission attributed to Ho 3+ f-f transition, under 360 nm excitation. Compared to the single Ho 3+ -doped sample, the Vis PL intensity of the codoped sample was increased by nearly 13.8 times, and an enhanced photoluminescence quantum yield (PLQY) of 87.45 % was achieved. The PL enhancement is attributed to the partial substituting of Na + with Ag + , leading to an efficient STE emission, and the more energy transition from STE to Ho 3+ . Moreover, the synthesized phosphor exhibits good stability in thermal and atmospheric environments. White light-emitting diode (WLED) is fabricated by employing Cs 2 Na 0·997 Ag 0·003 Bi 0.935 Ho 0.065 Cl 6 on near-ultraviolet (n-UV) LED chips, achieving a color rendering index (CRI) of 95.0 and correlated color temperature (CCT) of 3814 K. Anti-counterfeit patterns and the application for night vision monitoring were also discussed. This study inspires the designing of high-quality phosphors of rare earth-doped DPs and expands the multi-domain luminescence applications of halide DPs.
研究领域:
材料科学
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光学工程
·
稀土材料
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2023
·
IF 3.9
Mengjia Zhang,Changchun Ding,Bin Duan,Yuxiang Wu,Yongqiang Li,Jin Wei,Fengyi Wang,Junshan Hu
The upconversion luminescence (UCL) of inorganic materials doped with activators and sensitizers has great application, but its luminescence intensity always impose restrictions on its development. Herein, an obvious enhancement in luminescence intensity of the WO 3 : Yb 3+ , Ho 3+ phosphor was realized through non-equivalence substitution of Bi 3+ ions. The single pure phase of the synthesized WO 3 : Yb 3+ , Ho 3+ , and Bi 3+ phosphors has been confirmed by the XRD pattern. The morphology of phosphors and valence state of elements have been performed by SEM and XPS techniques. The sample on excitation with 980 nm performs forceful green emission and weak red emission at 543 nm and 662 nm, separately. The concentrations for doped Yb 3+ and Ho 3+ to obtain the optimal UCL in WO 3 are 8% and 1%, respectively. The optimized doping concentration for Bi 3+ ions is 3%. Compared to samples without Bi 3+ ions, the Yb 3+ /Ho 3+ /Bi 3+ doped WO 3 obtains 1.59 and 2.33 times increase in emission intensity of green and red, respectively. We also explored the UCL mechanism and enhancement mechanism on the basis of the power dependency, the UCL and the downshift luminescence. These results based on Yb 3+ /Ho 3+ UCL phosphors research is of great significance.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2018
·
IF 2.32
Rui Wang,Maohui Yuan,Chaofan Zhang,Hongyan Wang,Xiaojun Xu
Transition metal ions (e.g. Mn 2+ ) and lanthanide co-doped upconversion (UC) materials have attracted wide attention in recent years due to their promising application in multicolor display. Here, we report the hydrothermal synthesis and characterization of Mn 2+ doped monodisperse CaF 2 :Yb 3+ /Ho 3+ microspheres . The results of X-ray diffraction (XRD) revealed that Mn 2+ doping does not change the cubic phase of CaF 2 material but will lead to diffraction peaks shifting slightly towards higher angle due to the substitution of larger Ca 2+ by the relatively smaller Mn 2+ . Under the excitation of 980 nm continuous wave (CW) laser, these microspheres exhibit green-yellow-red tuning colors and remarkable enhancement of both red to green ratio (R/G) and red to blue ratio (R/B) when increasing Mn 2+ concentration from 0 to 30 mol%. The energy migration process between Ho 3+ and Mn 2+ was proposed and supported by time-decay and power dependence measurements of Ho 3+ UC emission. These upconversion materials may have potential applications in optical devices , color display, nanoscale lasers and biomedical imaging.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Science China-Materials
·
2023
·Vol. 66
·期 9
·3696-3705
·
IF 8.1
Wang Yang,Gao Feng,Zhou Shuai,Hu Po,Fu Jiajun
Lanthanide-doped upconversion nanoparticles (UCNPs) have been extensively investigated owing to their unique advantages. So far, the most favored modality of UCNPs is still the classical Yb–A (where A refers to Er 3+ , Tm 3+ , and Ho 3+ )-coupled nanosystems under 980-nm excitation. However, the frequently used Yb 3+ ion with the single-excited 2 F 5/2 state can barely transfer energy to other acceptors owing to its lack of matched excited levels. Herein, a novel strategy is proposed for energy transfer via Ho 3+ as a bridge ion coupling donor-acceptor pairs (e.g., Yb 3+ –Nd 3+ ), where little direct energy transfer occurs, and the involved energy transport mechanisms are investigated. The findings reveal that long-distance energy transportation can occur in the Ho 3+ sublattice owing to the energy migration capability of Ho 3+ and that Ho 3+ as a bridge ion can realize interparticle energy transfer for upconversion luminescence. Moreover, well-designed NaYbF 4 :40%Ho@NaYF 4 :10%Nd core-shell nanoparticles with multimode responsiveness can emit different colored lights under varying excitation wavelengths, which are demonstrated in high-level anticounterfeiting and information identification. Therefore, this work paves a new way to understand the functionality of the Ho 3+ bridge in energy transfer upconversion and offers strategies for broadening energy transfer pathways and finely manipulating photon upconversion.
研究领域:
材料科学
·
光学
·
纳米技术
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产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2024
·
IF 5.7
Yanyang Li,Huimin Du,Yue Ma,Meifang Liu,Jian Zou,Shentang Wang,Jun Yang,Shanshan Hu,Jun Lin
The existence of energy transfer channels from the self-trapped exciton (STE) emission to lanthanide (Ln3+) ions in double perovskites (DPs) opens up new possibilities for high security anti-counterfeiting applications. In the present investigation, we synthesized Sb3+/Ho3+/Er3+ doped Cs2NaGdCl6 rare-earth-based DPs using a simple solvothermal method, whose luminescence could be quenched by water and restored after drying. The efficient down-shifting (DS) red emission from the 4f–4f transition of Ho3+ was enhanced 8-fold due to the energy transfer of STEs → Ho3+ ions via Sb3+ sensitization. The DS and up-conversion (UC) dual-mode multicolor emissions were obtained by further introducing Er3+. Specifically, the DS luminescence of the tri-doped sample under the UV region and that under 448 nm irradiation were white and red, respectively; and the UC luminescence under 980 nm irradiation was green. In view of their stimulus response to water and dual-mode multicolor luminescence properties, advanced anti-counterfeiting materials based on the obtained samples were designed.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子