OPTICAL MATERIALS
·
2024
·
IF 3.8
Jian He,Bowen Wang,Changshuai Gong,Xuejiao Wang,Qiushi Wang,Ji-Guang Li
Gd 3+ co-doping is effective to enhance the photoluminescence of rare earth activators in various host due to energy transfer, however, it is rarely reported via such strategy to regulate persistent luminescence properties. In this work, Gd 3+ was co-doped into the SrLaAlO 4 : Tb persistent luminescence phosphors, and it is found that the photoluminescence and persistent luminescence of the products can be simultaneously improved. The results indicate that as the doping concentration of Gd 3+ increases, the particle diameters increase which contributes the increased luminescence. Additionally, an energy transfer process from Gd 3+ to Tb 3+ ions was observed, which enhances the emission of Tb 3+ ions. Furthermore, the persistent luminescence properties of the synthesized phosphors were improved. When the UV light source is turned off, the persistent luminescence of SrLaAlO 4 : 0.03Tb 3+ , x Gd 3+ ( x = 0.00–0.97) can last for more than 2 h, which is 100 % enhanced compared to SrLaAlO 4 : 0.03Tb 3+ . The trap distribution of SrLaAlO 4 : 0.03Tb 3+ , x Gd 3+ ( x = 0.00–0.97) phosphors was analyzed by thermoluminescence. It is found that after the substitution of La 3+ with Gd 3+ , the trap position shifted towards higher temperatures and the trap concentration increased. The initial intensity of the persistent luminescence was also enhanced after Gd 3+ co-doping. Based on the experimental findings, the luminescence and persistent luminescence mechanism of SrLaAlO 4 : 0.03Tb 3+ , x Gd 3+ ( x = 0.00–0.97) phosphors were described and discussed.
研究领域:
材料科学
·
光学
✓ 已验证
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
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2025
·
IF 3.5
Lanwei Qiu,Haochang Ye,Guangting Xiong,Wei Zhang,Yirong Huang,Qiuzhi Liang,Canhui Pan,Jinquan Chen,Zuyong Feng
Orange-red KLa(WO 4 ) 2 phosphors co-doped with Sm 3+ -Gd 3+ were synthesized via high-temperature solid-state reaction. Phase purity and crystal structure were confirmed by XRD, while SEM revealed non-uniform particle distribution. XPS verified elemental composition and suggested the chemical states of dopants. Under 403 nm excitation, KLa(WO 4 ) 2 : Sm 3+ exhibited intense orange–red emissions, dominated by the 4 G 5/2 - 6 Hᵢ (i = 5/2, 7/2, 9/2, 11/2) transition from 500 to 750 nm. Substitution by Gd 3+ lowers the local symmetry, as evidenced by the increased asymmetry ratio, resulting in a 1.88-fold increase in emission intensity. Notably, the optimized phosphor, KLa 0.8 Gd 0.15 (WO 4 ) 2 :0.05Sm 3+ , exhibits a high color purity (CP) of 99 % and excellent thermal stability retaining 85 % of its room-temperature emission intensity at 423K. When combined with a 405 nm InGaN chip, the fabricated LED displayed strong spectral overlap with chlorophyll and phytochrome absorption peaks, confirming its potential for plant-growth illumination.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2016
·
IF 7.145
Yunfei Xie,Wangmei He,Fang Li,Thalagalage Shalika Harshani Perera,Lin Gan,Yingchao Han,Xinyu Wang,Shipu Li,Honglian Dai
Biocompatible, biodegradable, and luminescent nano material can be used as an alternative bioimaging agent for early cancer diagnosis, which is crucial to achieve successful treatment. Hydroxyapatite (HAP) nanocyrstals have good biocompatibility and biodegradability, and can be used as an excellent host for luminescent rare earth elements. In this study, based on the energy transfer from Gd3+ to Eu3+, the luminescence enhanced imaging agent of Eu/Gd codoping HAP (HAP:Eu/Gd) nanocrystals are obtained via coprecipitation with plate-like shape and no change in crystal phase composition. The luminescence can be much elevated (up to about 120%) with a nonlinear increase versus Gd doping content, which is due to the energy transfer (6PJ of Gd3+ → 5HJ of Eu3+) under 273 nm and the possible combination effect of the cooperative upconversion and the successive energy transfer under 394 nm, respectively. Results demonstrate that the biocompatible HAP:Eu/Gd nanocrystals can successfully perform cell labeling and in vivo imaging. The intracellular HAP:Eu/Gd nanocrystals display good biodegradability with a cumulative degradation of about 65% after 72 h. This biocompatible, biodegradable, and luminescence enhanced HAP:Eu/Gd nanocrystal has the potential to act as a fluorescent imaging agent in vitro and in vivo.
研究领域:
材料科学
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生物医学工程
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DALTON TRANSACTIONS
·
2021
·Vol. 50
·期 43
·15688-15695
·
IF 4.39
Minghui Li,Jun Zhou,Ruoshan Lei,Huanping Wang,Feifei Huang,Shiqing Xu
Nowadays, there is enthusiastic effort to develop luminescent thermometers used for remote and high-sensitivity temperature readout over a wide sensing range. Herein, Pr3+ and Gd3+ co-doped ZrO2 nanocrystals are designed, prepared and investigated by XRD, Raman spectroscopy, XPS, TEM, EDS, DRS, PLE and PL spectroscopy. Upon 275 nm irradiation, the PL spectrum of ZrO2:Pr3+,Gd3+ is found to be composed of a narrow emission peak at 314 nm (Gd3+ 6P7/2–8S7/2), a broad defect-related emission band at 400 nm, and several emission peaks in the wavelength region of 585–700 nm (Pr3+ 1D2–3H4, 3P0–3H6, and 3P0–3F2), which exhibit different thermal responses owing to the effects of the various non-radiative relaxation processes and trap energy levels. Accordingly, the luminescence intensity ratio (LIR) between the Pr3+ 1D2–3H4 and Gd3+ 6P7/2–8S7/2 transitions demonstrates excellent relative sensing sensitivity values ((2.32 ± 0.01)% K−1–(8.32 ± 0.05)% K−1) and low temperature uncertainties (0.08 K–0.28 K) over a wide temperature sensing range of 303 K to 573 K, which are remarkably better than those of many other luminescence thermometers. What is discussed in the present study may be conducive to broadening the research region of RE3+ doped luminescence thermometric phosphors, especially for materials with rich 4f–4f transition lines and defect-related luminescence.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Yangqing Wu,Mei Wang,Shaolian Sun,Shan Shao,Ziyu Pan,Jinkai Li,Haoming Wei,Bingqiang Cao
X-ray excitation photodynamic therapy is a new photodynamic therapy mode that induces tumor cell apoptosis by indirectly stimulating photosensitizer on nanoparticles with X-ray as excitation light source and generating singlet oxygen. It solves the problem of light penetration in traditional photodynamic therapy and realizes the treatment of deep tumors. At present, the weak X-ray-induced luminescence restricts further development of X-ray photodynamic therapy. NaLuF 4 :Li + /Gd 3+ /Tb 3+ rare-earth nanoparticles with uniform size and regular morphology were synthesized by solvothermal method . The X-ray-induced luminescence intensity of NaLuF 4 :Li + /Gd 3+ /Tb 3+ NPs was improved by Li + and Gd 3+ ions co-doping. The light yield of NaLuF 4 :Li + /Gd 3+ /Tb 3+ NPs with 5% Li + ions doping was 1.4 times than that of reference sample due to the change of crystal field symmetry. Furthermore, the effective lifetime of persistent luminescence increased from 221.5 s to 251.9 s after 15% Li + ions doping. The thermoluminescence curves confirmed that the trap concentration was increased after Li + ions doping, which was responsible for enhancing persistent luminescence lifetime . Long persistent luminescence emission laid a foundation for further application in photodynamic therapy.
研究领域:
材料科学
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医学
·
生物技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2017
·
IF 2.686
Wangmei He,Yunfei Xie,Qingguo Xing,Peilong Ni,Yingchao Han,Honglian Dai
Herein, a polyacrylic acid sol-gel method was presented to synthesize rare earth doped calcium phosphate nanocrystals (RE-CaP) as cell bioimaging agent. The effects of calcination temperature, calcination time and PAA concentration on phase composition , morphology, size and luminescence were discussed. In addition, the hemolysis, cytotoxicity, cell uptake and cell imaging of resulting RE-CaP nanocrystals were investigated. Results show that the increases in calcination temperature and time promote the transformation of product from impure crystalline phase (CaCO 3 , CaO) to pure CaP phase. The rise of calcination temperature results in significant enhancement of luminescence intensity. PAA concentration does not influence the crystalline phase composition and its increase leads to a little increase in luminescence intensity. In addition, the co-doping of Gd 3+ improves the luminescence intensity of Eu 3+ emissions. This method achieves the doping of Eu 3+ ions in the crystallographic Ca 2+ I and Ca 2+ II sites of HAP with a preferable occupation at Ca 2+ II site. The resulting RE-CaP nanocrystals (PAA: 0.6 mg/mL, Eu/Gd = 2:1.5, 600 °C, 3 h) show good biocompatibility and can be easily uptaken by cancer cells. The internalized nanocrystals show stable and strong red luminescence under visible wavelengths excitation. In summary, PAA sol-gel method can be used to synthesize biocompatible RE-CaP luminescent nanomaterials for cell bioimaging.
研究领域:
材料科学
·
纳米技术
·
生物医学工程
·
细胞生物学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）