LUMINESCENCE
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2023
·Vol. 38
·期 8
·1465-1476
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IF 2.9
Sheng Wu,Puxian Xiong,Kexin Qin,Yao Xiao,Binli Xiao,Kang Chen,Dongliang Jiang,Yinzhen Wang
Mechanoluminescence (ML) materials have found potential applications in information storage, anti-counterfeiting, and stress sensing. Conventional stress sensing based on absolute ML intensity is prone to significant mistakes owing to the unpredictability of measurement surroundings. However, implementing a ratiometric ML sensing technique may considerably ameliorate this issue. In this study, a single activator-doped gallate material (LiGa 5 O 8 :Pr 3+ ) is proposed to determine the relationship between the ML intensity and the change in local positional symmetry that occurs when the material is subjected to stress. The sensing reliability of the ML intensity ratio under different factors (Force; Content; Thickness and Materials) is systematically analyzed, where the factor that has the greatest effect on the proportional ML is the concentration, with the ML intensity asymmetry ratio decreasing from 1.868 to 1.300 varying concentration at constant stress. The colour-resolved visualization of stress sensing is further realized, which opens a new path for a ratiometric ML-based strategy to improve the reliability of stress sensing.
研究领域:
材料科学
·
光学
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DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2021
·Vol. 31
·期 19
·2010685
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IF 18.808
Puxian Xiong,Bolong Huang,Dengfeng Peng,Bruno Viana,Mingying Peng,Zhijun Ma
Currently, most of the mechanoluminescence (ML) phosphors strongly depend on postirradiation stimulation using ultraviolet light (denoted as “UV exposure” from hereon) to show the ML. However, only a few transition metal cations are proven to be effective luminescence centers, which hinder the development of more ML phosphors. This study reports a self-recoverable deep-red-to-near-infrared ML using Cr 3+ -doped LiGa 5 O 8 phosphor with fully recoverable ML performance. The ML performance can be further optimized by tuning the trap redistributions by codoping the phosphor with Al 3+ and Cr 3+ cations. Theoretical calculations reveal the important role of Cr dopants in the modulation of local electronic environments for achieving the ML. Owing to the induced interelectronic levels and shallow electron trap distributions, the electron recombination efficiency is enhanced both through direct tunneling and energy transfer toward the dopant levels. Moreover, the ML of Cr 3+ -doped LiGa 5 O 8 can penetrate a 2-mm-thick pork slice, showing that it can have wide-ranging in vivo applications, including the optical imaging of intracorporal stress/strain distribution and dynamics. Therefore, this work fabricates a novel ML material with self-recoverable luminescence in an extended wavelength range, increasing the number of potential ML candidates and promoting the fundamental understanding and practical applications of ML materials.
研究领域:
材料科学
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生物医学工程
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光学成像
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分子探针
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转化医学
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DOI
高影响因子
Journal of Materials Chemistry C
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2024
·
IF 5.7
Min Jia,Xiangyu Zhang,Xue Yang,Zehao Lin,Dingjun Jia,Yuqiang Wang,Sining Yun,Dangli Gao
Multi-mode storage phosphors with photo/thermo/mechano-stimulated luminescence (PSL/TSL/ML) hold great potential applications in many fields such as biological imaging, human-machine interface, robotic manipulation, and stress/temperature visualization sensing. However, the physical mechanisms underlying this 'self-sustaining' luminescence are still debated, which in turn hinders the development of materials. Here, we demonstrated that the intrinsic defects such as the VO•• and Oi′′ in the matrix play an important role in the electronic structure and various physical properties of LiGa5O8 storage phosphor by combining first-principles calculations and experimental methods. Specifically, the intrinsic defects lead to the smaller bulk (B) and shear (G) modulus, Young’s moduli (E), Poisson’s ratio (v), B/G, and the bigger elastic anisotropy index (AU) and hardness (H) in three LiGa5O8 defect models, which is extremely advantageous for PSL/TSL/ML. We also demonstrate that the ML process, that is different from PSL/TSL processes, are intimately linked to the activation threshold of charge carriers in traps. This threshold can be lowered under axial stress by bandgap narrowing via weakening the binding force of polyhedral units to bind electrons in the converting process between mechanical energy and light energy under stress load. This study provides not only direct evidence for potential variation in ML process, but also guidance for designing the storage phosphors via defect engineering.
研究领域:
材料科学
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光学
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物理学
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DOI
高影响因子
Inorganic Chemistry Frontiers
·
2022
·Vol. 9
·期 16
·4022-4029
·
IF 7.779
Peng Zhang,Wanying Xie,Zhenbin Wang,Zenggang Lin,Xiuxiang Huang,Zhenghua Ju,Weisheng Liu
Long-persistent luminescence (PersL) materials have shown great promise on account of their diverse utilization in anticounterfeiting and encryption. Nevertheless, time-dependent dynamic multicolor afterglow is rarely reported, especially for single-component oxide-based materials. In this work, a series of LiGa5O8:Eu3+/Tb3+ phosphors exhibit time-dependent dynamic multicolor afterglow from blue to red or green over several seconds after ceasing the excitation. Both experimental and computational data confirm that the color evolution results from different energy transfer processes between traps and luminescent centers. The processes are probably controlled by thermally activated exciton diffusion and the electron tunneling effect. This dynamic multicolor afterglow of LiGa5O8 phosphors allows their applications in anticounterfeiting and encryption with high security levels.
研究领域:
材料科学
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光学
·
加密技术
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防伪技术
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DOI
高影响因子
Advanced Optical Materials
·
2021
·Vol. 9
·期 13
·2100137
·
IF 9.926
Na Zhang,Birong Tian,Zhaofeng Wang,Andrew T. Smith,Zhidong Ma,Zhonghua Xue,Luyi Sun
The distinctive crystal characteristics of undoped LiGa 5 O 8 allow the production of abundant defects and traps in the structure, contributing to attractive luminescent properties. In this work, the mechanoluminescent pathways of LiGa 5 O 8 are demonstrated in terms of the defect induced localized energy levels and trap levels, which are further optimized by adjusting the synthesis atmosphere. The results suggest that the LiGa 5 O 8 synthesized under a reducing atmosphere exhibits an extremely intense mechanoluminescence, which is even better than that of commercial ZnS:Cu. Because of the existence of shallow trap with the spontaneous transfer activity at room temperature, the mechanoluminescence of LiGa 5 O 8 can also exhibit a persistent behavior, overcoming the transient emitting problem in most of the previous mechanoluminescent materials. In addition, the mechanoluminescence of LiGa 5 O 8 can be easily and quickly recovered by refilling the energy in traps. As a result, the undoped LiGa 5 O 8 is confirmed to be an efficient material with intense, persistent, and recoverable mechanoluminescence, which is promising to substitute the doped ones for various applications.
研究领域:
材料科学
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发光材料
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机械发光
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固态化学
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DOI
高影响因子
Materials Today Chemistry
·
2025
·
IF 6.7
Yuan Wang,DouDou Zhang,Hao song,Xiuxia Yang,Zhichao Liu,Yuankang Wang,Jie Yu,Xu Tian
X-ray scintillators are crucial for medical, industrial, and security imaging systems. However, achieving dual-mode of real-time and delayed imaging within a single matrix still faces challenges. Herein, LiGa 5 O 8 : Tb 3+ was successfully synthesized by the high-temperature solid-phase method. By controlling the atmosphere and optimizing the Li + /Ga 3+ ratio, the trap structure of LiGa 5 O 8 : Tb 3+ spinel phosphors is effectively adjusted, which achieved excellent dual-mode imaging. The air-synthesized Li 1.6 Ga 5 O 8 :4 %Tb 3+ exhibits intense X-ray excited persistent luminescence (X-PersL, 595 nm), while the sample of LiGa 5 O 8 :Tb 3+ reduced in H 2 /N 2 shows enhanced radioluminescence (RL) without X-PersL. This precise manipulation of anti-occupancy defects controls the charge trapping/detrapping dynamics, enabling switchable RL (real-time imaging) and X-PersL (delayed imaging) modes through the single Tb 3+ ions emission. The result resolves the incompatibility between prompt and persistent X-ray responses in conventional scintillators. The defect-regulation method establishes a universal strategy for developing scintillators compatible with complex operational demands, advancing high-performance X-ray imaging technologies.
研究领域:
材料科学
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生物医学工程
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影像学
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辐射探测
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无机功能材料
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2026
·
IF 6.7
Yunan Lin,Peiyuan Zhuang,Xiaoting Gao,Wudeng Wang,Guorui Li,Zheng Wei,Yanjie Zhang,Jingjie Yu
With the rapid advancement of information technology, anti-counterfeiting requirements across diverse scenarios have become increasingly stringent, thereby spurring significant interest in multifunctional luminescent materials integrating photochromic and luminescence-tunable properties. However, traditional anti-counterfeiting technologies mainly depend on single color emitting phosphors, hardly meeting the requirements of high-level encryption and anti-counterfeiting. Herein, CsPbBr 3 /LiGa 5 O 8 : Eu 3+ perovskite quantum dots (PQDs) phosphors with red-green bicolor emission have been successfully developed via the solution impregnation method. The CsPbBr 3 PQDs uniformly supported on the surface of LiGa 5 O 8 : Eu 3+ phosphors can effectively endure high-temperature calcination and maintain the average particle size of ∼5.0 nm even after calcination at 400°C, avoiding the serious problem of aggregation and luminescence quenching of PQDs at high temperatures. CsPbBr 3 /LiGa 5 O 8 : Eu 3+ PQDs phosphors exhibit a red emission peak at 620 nm under excitation at 254 nm and a green emission peak at 530 nm under excitation at 365 nm, attributed to the transitions of Eu 3+ ions and CsPbBr 3 PQDs, respectively. Notably, the green emission intensity of CsPbBr 3 /LiGa 5 O 8 : Eu 3+ PQDs phosphors calcined at 400°C increases by 36 times compared to the uncalcined sample, attributed to the fact that the bromine vacancies in CsPbBr 3 quantum dots are passivated by the oxygen of LiGa 5 O 8 lattice. The fluorescence lifetime rises by ∼900 %, from 19.05 ns of uncalcined sample to 171.43 ns of CsPbBr 3 /LiGa 5 O 8 : Eu 3+ PQDs phosphors calcined at 400℃, owing to suppressed electron-hole recombination via PQDs loading. X-ray photoelectron spectroscopy (XPS) results further verify that 400°C calcination plays a significant role in boosting the green emission of samples. Based on the unique red-green dual-color emission characteristics of the CsPbBr 3 /LiGa 5 O 8 : Eu 3+ PQDs phosphors, an anti-counterfeiting strategy encompassing invisible labels and information encryption via binary and Morse codes is proposed. Therefore, CsPbBr 3 /LiGa 5 O 8 : Eu 3+ PQDs phosphors hold potential applications in invisible pattern display, tunable photochromism, information encryption and other related fields.
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产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2023
·
IF 4.6
Zishuo Yi,Peng Liu,Xia Liu,Yan Xu
Persistent luminescence (PersL) materials with impressive superiorities in optical performance have shown tremendous potential for information encryption application. Herein, a Bi3+-doped LiGa5O8 PersL material is facilely synthesized by a simple solid-state reaction. Site selective and preferential occupation of Bi3+ ions at distinct Ga3+ and Li+ polyhedra sites in LiGa5O8 endows it with a bimodal emission at 511 and 718 nm upon UV excitation at 254 nm. After removing the light source, an intense red afterglow was observed due to the generation of more and deeper traps classified as the oxygen vacancy defect (VO••) and the impurity defect (BiLi••). It is rarely reported in inorganic phosphors to achieve the Bi3+ single doping-activated red PersL. The LiGa5O8:x% Bi3+ (with x = 0.5–5.0) samples also exhibit tunable PL and time-dependent PersL properties. Combined with the Morse Code, a multiple information encryption model based on the abnormal optical properties of LiGa5O8:x% Bi3+ (x = 0, 0.5, and 5.0) samples was designed for high-level dynamic anticounterfeiting. These achievements further validate the use of the Bi3+ single doping strategy to explore excellent PersL materials and expand their multifunctional optical applications.
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产品关联
DOI
PubMed
高影响因子
Advanced Optical Materials
·
2019
·Vol. 7
·期 24
·1901107
·
IF 7.125
Puxian Xiong,Mingying Peng,Kexin Qin,Feifei Xu,Xingyi Xu
Here, a novel multifunctional phosphor of Li 1− x Ga 5 O 8 : x Pr 3+ is reported. The crystal structure, mechanoluminescence (ML), persistent luminescence (PersL), photoluminescence (PL) and photoluminescence excitation (PLE) are systematically studied. LiGa 5 O 8 emits blue PersL peaked at 437 nm after irradiation by a 254 nm lamp for 10 s, and corresponding PersL can be observed for 30 min by naked eyes. In the same case, the PersL from Li 0.995 Ga 5 O 8 :0.005Pr 3+ covers visible to near-infrared lights (400–1000 nm) which can persist for 120 min. Thermoluminescence analysis shows Pr 3+ doping not only increases the shallower trap (0.73 eV) concentration by at least 20 times but also helps the formation of deeper trap centers (0.87 eV). The differences between ML and PersL spectra reveal the selective effects of mechanical stimuli on the transitions of Pr 3+ ions. In the end, the fabrication of an intelligent PersL quick response code (QR-code) permits optical information write-in after irradiation by a 254 nm lamp and then cryptical information of “SCUT” can be read out by thermal stimulation which shows the potential in information storage. Moreover, the biological tissues penetration experiments and cytotoxicity tests are carried out to display the potential of PersL in bioimaging.
研究领域:
材料科学
·
发光材料
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光学存储
·
生物医学成像
·
智能材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）