MOLECULES
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2019
·Vol. 24
·期 7
·1253
·
IF 3.06
Qingrui Zhang,Xiuyun Yang,Ruiping Deng,Liang Zhou,Yang Yu,Yunhui Li
A polyhedral oligomeric silsesquioxanes (POSS) modified 8-hydroxyquinoline derivative (denoted as Q-POSS) was synthesized and used as a ligand to coordinate with lanthanide ions to obtain a series of lanthanide complexes Ln(Q-POSS)3(Ln = Er3+, Yb3+, Nd3+). The as-prepared lanthanide complexes have been characterized by FT-IR, UV–Vis, and elemental analysis. All these complexes showed the characteristic near-infrared (NIR) luminescence originated from the corresponding lanthanide ions under excitation. Compared with the unmodified counterparts LnQ3(HQ = 8-hydroxyquinoline), the Ln(Q-POSS)3complexes showed obviously increased emission intensity, which was ascribed mainly to the steric-hindrance effects of the POSS moiety in the ligands. It is believed that the POSS group could suppress undesired excimer formation and intermolecular aggregation, thus decreasing the concentration quenching effect of the corresponding lanthanide complexes.Keywords:lanthanide complexes;polyhedral oligomeric silsesquioxanes;near-infrared luminescence
研究领域:
材料化学
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光物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Qincan Ma,Jinyuan Zhang,Junhao Ma,Shuang Fu,Ziyang Ren,Xianzhong Lin,Gechuanqi Pan,Yueli Zhang
Novel rare-earth borate luminescent materials demonstrate considerable potential for optoelectronic applications, yet their luminescent efficiency remains constrained by concentration quenching arising from high activator concentrations. Herein, a new type of non-centrosymmetric rare-earth borate Sr 3 BiY 3-x Eu x B 4 O 15 phosphors (x = 0.1, 0.3, 0.5, 0.7, 1.0) were synthesized via Y 3+ /Eu 3+ alloying. Such phosphors achieved enhanced luminescence while maintaining ultra-high activator concentrations. The research innovatively elucidates the dual-mechanism anti-concentration quenching within the system. Under 250 nm excitation, the highly efficient energy transfer from Bi 3+ sensitizer to Eu 3+ activator optimizes excitation energy migration pathways. This results in a 1.55-fold enhancement in relative emission intensity for the Sr 3 BiY 2.5 Eu 0.5 B 4 O 15 phosphor, accompanied by a marked improvement in photoluminescence quantum yield from 86.71% (Sr 3 BiY 2.9 Eu 0.1 B 4 O 15 ) to 96.76%. Under 394 nm excitation, the chain-like channels of Eu 3+ ions induced by the non-centrosymmetric configuration in the crystal significantly enhance cross-relaxation caused by the electric multipole interaction. Electron redistribution from the 5 L 6 state of one Eu 3+ to the 5 D 6 state of neighboring Eu 3+ via cross-relaxation elevates the population of 5 D 6 -excited electrons, thereby amplifying the relative emission intensity of Sr 3 BiY 2 EuB 4 O 15 by a factor of 4.54. Thermal quenching analysis demonstrates that Sr 3 BiY 2.5 Eu 0.5 B 4 O 15 retains 60% of its initial luminescence intensity at 503 K. This material integrates good thermal stability with multifunctional applicability, positioning it suitable for red light-emitting diode, optical display, and digital encryption fields. This work provides new insights into the structural-performance regulation to break the bottleneck of concentration quenching in novel rare-earth luminescent materials.
研究领域:
材料科学
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光学功能材料
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固态化学
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发光物理
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无机非金属材料
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2023
·Vol. 35
·期 41
·2306517
·
IF 29.4
Wenge Xiao,Endale T. Basore,Guojun Zheng,Xiaofeng Liu,Beibei Xu,Jianrong Qiu
The brightness of doped luminescent materials is usually limited by the ubiquitous concentration quenching phenomenon resulting in an intractable tradeoff between internal quantum efficiency and excitation efficiency. Here, an intrinsic suppression of concentration quenching in sensitized luminescent systems, by exploiting the competitive relationship between light emitters and quenchers in trapping excitation energies from sensitizers, is reported. Although Cr 3+ sensitizers and trivalent lanthanide (Ln 3+ , Ln = Yb, Nd, and Er) emitters themselves are highly susceptible to concentration quenching, the unprecedentedly high-brightness luminescence of Cr 3+ –Ln 3+ systems is demonstrated in the short-wave infrared (SWIR) range employing high concentrations of Cr 3+ , whereby a record photoelectric efficiency of 23% is achieved for SWIR phosphor-converted light-emitting diodes, which is about twice as high as those previously reported. The results underscore the beneficial role of emitters in terminating excitation energies, opening up a new dimension for developing efficient sensitized luminescent materials.
研究领域:
材料科学
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光学
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光子学
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DOI
高影响因子
Coatings
·
2025
·Vol. 15
·期 9
·1012
·
IF 2.8
Shijian Sun,Mengquan Liu,Zheng Li,Junqiang Cheng,Dechuan Li
Hollow dendritic Na4La2(CO3)5crystals doped with Sm3+ions were synthesized with sodium carbonate using a hydrothermal method. The unique lifetime of Sm3+enables the optical measurement of luminescent ion content. The X-ray diffraction spectrum indicates that the nanocrystals maintain structural stability with a hexagonal arrangement, even when the concentration of Sm3+reaches 50 at.%. As the concentration of Sm3+increases, the emission intensity of Na4(La1−xSmx)2(CO3)5first rises and then falls. The maximum emission intensity of the fluorescent powder occurs at a Sm3+concentration of 0.04. Beyond this concentration, concentration quenching takes place, primarily due to electric dipole–dipole interactions. Using an excitation wavelength of 404 nm and monitoring at 596 nm, the fluorescence lifetime of Na4(La1−xSmx)2(CO3)5shows a strong dependence on Sm3+concentration, which can be described by a precise equation. Over the range of Sm3+concentrations from 0.005 to 1, the lifetime decreases from 3.126 ms to 0.023 ms. Therefore, optical monitoring of fluorescent powders is crucial for confirming the composition of coatings used in applications such as solid-state lighting and anti-counterfeiting, by utilizing the relationship between lifetime and doping concentration.
研究领域:
材料科学
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光学材料
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发光光谱学
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固态化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
·Vol. 44
·期 2
·1731-1736
·
IF 2.986
Jingbo Yu,Qian Zhang,Yi Gu,Anxian Lu
In this study, phosphate glasses embedded with Fe 2 O 3 quantum dots were prepared via a conventional melt quenching technology with further heat treatment. The effect of Fe 2 O 3 content on the structural, optical and magneto-optical properties was investigated. The results showed that the addition of Fe 2 O 3 had no obvious influence on the structure units that built up the host glass and the amorphous nature of glass. In the glass matrix , the existence of Fe 2 O 3 quantum dots was confirmed by high resolution transmission electron microscope . Meanwhile, optical study clearly demonstrated a red shift in optical cut-off wavelength resulted from the size quantization effect. The highest Verdet constant (22.33°/T-cm) was measured for the glass containing 1 mol% Fe 2 O 3 , which was ~ 7 times higher than that of the glass matrix. As the increment of Fe 2 O 3 contents, a phase evolution of Fe 2 O 3 quantum dots from amorphous phase to γ-Fe 2 O 3 phase was recorded due to the Ostwald Ripening effect. Interestingly, a concentration quenching phenomenon in Verdet constant was observed along with the phase evolution of Fe 2 O 3 quantum dots. When the content of Fe 2 O 3 is up to 2 mol%, the glass exhibited paramagnetism with the Verdet constant of − 2.833°/T-cm. This finding can provide a new idea for the development of quantum dot embedded magneto-optical glass.
研究领域:
材料科学
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磁光材料
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纳米材料
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无机非金属材料
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光学玻璃
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凝聚态物理
✓ 已验证
DOI
高影响因子
JOURNAL OF RARE EARTHS
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2023
·
IF 4.9
Youfa Tai,Ruirui Cui,Jun Zhang,Chunkai Wang,Tingyu Zhao,Beiqiao Zhang,Chaoyong Deng
Novel orange-red Sr 2 GdSbO 6 : x Eu 3+ ( x = 0, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6) phosphors were successfully prepared by the traditional high-temperature solid-state method. The results of Rietveld refinement, energy dispersive spectroscopy (EDS) spectrum and elemental mapping demonstrate that Eu 3+ successfully replaces the Gd 3+ sites and distributes uniformly in the particles of phosphors. The luminescence properties of Sr 2 GdSbO 6 :Eu 3+ phosphors were investigated in detail. The emission spectra of the strongest emission peak is the 5 D 0 → 7 F 1 (593 nm) transition, which can emit orange-red light under 393 nm excitation. When the doping concentration of Eu 3+ ions is x = 0.2, the luminescence intensity of the phosphors reaches the highest. The detailed mechanism of concentration quenching is attributed to dipole-dipole interaction. The thermal stability values of Sr 2 GdSbO 6 :0.2Eu 3+ phosphors are 87%, 82% and 114% under 393, 467 and 527 nm excitations, respectively. The causes of the abnormal thermal quenching under 527 nm excitation were analyzed. Based on the abnormal thermal quenching under 527 nm excitation, the optical thermometry properties of Sr 2 GdSbO 6 :0.2Eu 3+ phosphors were investigated by fluorescence intensity ratio (FIR) technique, and appreciable relative sensitivity was obtained. The results suggest that Sr 2 GdSbO 6 :0.2Eu 3+ phosphors can be potentially applied to w-LEDs and optical thermometers.
研究领域:
材料科学
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光学
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磷光材料
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发光材料
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光学传感
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2017
·Vol. 46
·期 44
·15373-15385
·
IF 4.029
Daqin Chen,Min Xu,Mengfan Ma,Ping Huang
In upconversion nanocrystals where Er3+ acts as the activator, concentration quenching will easily occur when the content of Er3+ is high (generally >5mol%), and the Er3+ spatial distribution which is a key factor affecting the concentration quenching is an important issue that must be considered. Herein, we selected Yb:NaErF4 as a light-emitting layer and investigated its upconversion performance and temperature sensing behaviors in two kinds of core–shell nanoarchitectures. Yb3+ and Er3+ activators were distributed in a three-dimensional sphere and two-dimensional thin layer in Yb:NaErF4@Yb/Nd:NaYF4@NaGdF4 and NaGdF4@Yb:NaErF4@Yb/Nd:NaYF4@NaGdF4 core–shell nanocrystals, respectively. The difference in Er3+ spatial distribution in the core–shell structure resulted in significant modification of red-to-green ratios and decay behaviors upon excitation at 376 nm, 808 nm, 980 nm and 1532 nm, and the related mechanisms were systematically investigated. In addition, the spatial distribution of Er3+ was demonstrated to have no obvious effect on the transitions of Er3+ thermally coupled 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 and the relative sensitivity for temperature determination under 808 nm laser excitation.
研究领域:
材料科学
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纳米技术
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光学
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温度传感
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产品关联
DOI
PubMed
高影响因子
Scientific Reports
·
2019
·Vol. 9
·期 1
·1-9
·
IF 4.011
Liu Ning,Mei Lefu,Liao Libing,Fu Jie,Yang Dan
What ideal w-LED phosphors always aim to do is to achieve a single phase near-sunlight emission phosphor simultaneously with both high luminescence efficiency and high thermal stability at operation temperature. And It is well known that apatite compound phosphors are one of the most promising optical materials to realize those above because of their unique structure enhanced luminescence properties and thermal stability. Here, we synthesized a co-doped single phase apatite phosphors Ca 2 La 8 (SiO 4 ) 6 O 2 :Dy 3+ /Sm 3+ (CLSO:Dy 3+ /Sm 3+ ) for white light emission, which was provided with excellent thermal stability and of which luminescence intensity at 150 °C still was 92 percentage of that at room temperature. Moreover, X-ray diffraction technique, Fourier transform infrared spectroscopy, scanning electron microscope were employed to characterization of phase structure and morphology, and consequently pure apatite structure and gravel-like morphology of phosphors were proved. Analysis of photoluminescence spectra indicated that concentration quenching effect exist in single-doped CLSO:Dy 3+ phosphors owing to dipole-dipole interaction between Dy 3+ ions. It is revealed that maybe exist Dy 3+ ↔ Sm 3+ bilateral non-radiative energy transfer processes in Dy 3+ /Sm 3+ co-doped CLSO system by PL spectra and decay curves. And variation of Sm 3+ ion concentration can control color emission, namely CIE chromaticity coordinates and correlated color temperature, finally to achieve white light emission (0.309,0.309) with CCT 6848 K, able to be a potential candidate for commercial lighting applications.
研究领域:
材料科学
·
光电
·
固体物理
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）