CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Tianshuai Lyu,Pieter Dorenbos,Canhua Li,Silei Li,Jian Xu,Zhanhua Wei
It is challenging to rational design persistent luminescence and storage phosphors with high storage capacity of electrons and holes after X-ray charging. Such phosphors have potential applications in anti-counterfeiting and X-ray imaging. Here we have combined vacuum referred binding energy diagram (VRBE) construction, photoluminescence spectroscopy, and thermoluminescence to study the trapping processes of charge carriers in NaYGeO 4 . In NaYGeO 4 :0.004Bi 3+ and NaYGeO 4 :0.004Bi 3+ ,0.005Ln 3+ (Ln = Tb or Pr), Bi 3+ appears to act as a shallow electron trap, while Bi 3+ and Ln 3+ act as deep hole trapping and recombination centres. We will show how to experimentally determine the VRBE in the Bi 2+ 2 P 1/2 ground state in NaYGeO 4 and NaLuGeO 4 by thermoluminescence study. The electron trap depth produced by Bi 3+ codopant in NaLu 1-x Y x GeO 4 :0.003Bi 3+ ,0.008 Tb 3+ can be adjusted, by increasing x, resulting in conduction band engineering. By combining Bi 3+ as an electron trap and Bi 3+ and Tb 3+ as the hole traps, excellent X-ray charged afterglow phosphors were developed. The integrated TL intensity of the optimized NaYGeO 4 :0.004Bi 3+ and NaYGeO 4 :0.003Bi 3+ ,0.008Tb 3+ after exposure to X-rays is about 4.5 and 1.1 times higher than that of the state-of-the-art BaFBr(I):Eu 2+ storage phosphor. Intense initial Tb 3+ 4f → 4f afterglow appears in NaYGeO 4 :0.003Bi 3+ ,0.008Tb 3+ and more than 40 h afterglow is measurable in NaYGeO 4 :0.004Bi 3+ and NaYGeO 4 :0.003Bi 3+ , 0.008 Tb 3+ after X-ray charging. We will show proof-of-concept anti-counterfeiting and X-ray imaging applications by using the developed afterglow phosphors and CsPbI 3 quantum dots. This work not only provides experimental evidence on the VRBE in the Bi 2+ 2 P 1/2 ground state in NaYGeO 4 , but also shows how to design and develop good afterglow phosphors for anti-counterfeiting and X-ray imaging by deeply studying and controlling the trapping processes of charge carriers in bismuth and/or lanthanides doped inorganic compounds.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
Materials Today Chemistry
·
2024
·
IF 6.7
Chaoyang Jia,Dangli Gao,Zhigang Wang,Xiangyu Zhang,Sining Yun,Jin Zhong Zhang,Xiaojun Wang
Persistent luminescence (PersL) phosphors, identified as ideal candidates, hold immense promise for information storage and encryption. However, practical storage and encryption technology using these phosphors remains uncommon due to their weak luminescence intensity and the inconvenience of light sources used in encryption and decryption processes. Here, we have developed Sr 2 MgSiGeO 7 :Eu 2+ ,Mn 2+ ,Dy 3+ phosphor with a super-long PersL beyond 100 h, the higher charge storage capacity and PersL efficiency (17 %) than commercial SrAl 2 O 4 :Eu,Dy phosphors by introduction of co-dopant Mn 2+ . This phosphor exhibits rapid and efficient charging capability when exposed to various light sources such as sunlight, light-emitting diode, mobile phone and computer screen. To explain the high charge storage capacity and super-long PersL, we propose a novel trap mechanism based on hole-electron defect pair trap structures. Notably, this phosphor as an anti-counterfeiting material demonstrates high-order encryption by the adding specific information writing process via temperature management. This study provides a new paradigm for future design of PersL phosphors and luminescent anti-counterfeiting.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Yuanyuan Hu,Dangli Gao,Jia Yu,Xue Yang,Xiangyu Zhang,Sining Yun,Xiaojun Wang
Conventional persistent luminescent phosphors face a significant challenge in developing a single material for multi-color anti-counterfeiting. In this study, a wide range of Cr 3+ activated gallium germanate-based persistent phosphors are successfully synthesized using high-temperature solid phase approach. By incorporating Cr 3+ and Er 3+ as dual emitting centers, and utilizing Yb 3+ as a sensitizer and electron traps, the resulting phosphors exhibit an exceptional combination of photoluminescence , up-conversion luminescence, persistent luminescence, photo/thermo-stimulated luminescence, followed by photo-stimulated persistent luminescence in a single material system. Beyond its multi-mode emissions, the luminescence color output can be conveniently controlled by adjusting annealing time, Yb 3+ ion doping concentration, excitation wavelength, or excitation power. A systematic study of trap distribution related to PersL has been conducted by regulating annealing temperature, time, doping concentration and type. The responding multi-mode luminescent mechanisms are also proposed. Particularly, these phosphors demonstrated outstanding performance as security labels in advanced anti-counterfeiting applications. This research holds the potential to inspire the design and development of more intricate luminescence anti-counterfeiting materials and technologies.
研究领域:
材料科学
·
光学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Optical Materials
·
2024
·
IF 8
Shanshan Zhao,Dechao Yu,Benchun Li,Saima Kanwal,Tiantian Shen,Jincheng Wu,Songlin Zhuang,Dawei Zhang
The development of blue/green/red tricolor upconversion (UC) phosphors under invisible light irradiation has attracted significant interest in emerging applications such as anti-counterfeiting, three-dimensional (3D) optical data storage, and solid-state 3D displays. In this study, a series of LiYO 2 :RE 3+ ,Yb 3+ (RE = Tm, Ho, Eu) phosphors are successfully prepared via first precipitation process followed by calcination, and completely optimized for efficient tricolor UC luminescence with 980 nm laser excitation. Mechanisms involving two- or three-photon absorption processes and low-phonon-energy-suppressed multi-phonon relaxation have been proposed for Ho 3+ (Eu 3+ )/Yb 3+ and Tm 3+ /Yb 3+ codoping, respectively. In addition, the RE 3+ (Yb 3+ ) concentration-induced phase transition of the LiYO 2 host is discussed for interesting possibilities in spectral regulation. Based on the broad color gamut achieved by the tricolor UC phosphor mixture, homochromatic and polychromatic metamerisms are experimentally fabricated via screen printing for high-level anti-counterfeiting and information security. Moreover, for a proof-of-concept demonstration, prototypes of 3D optical data storage and volumetric displays are constructed by embedding tricolor UC mixtures and their 3D printed patterns in polydimethylsiloxane. It is believed that the continuous exploration of tricolor UC under invisible light excitation for metamerism anti-counterfeiting and 3D displays can promote the development of high-level information security and advanced volumetric display technologies.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2025
·
IF 4.6
Xucai Zhao,Qingqing Yu,Lili Zhang,Rongfei Wei,Hai Guo
As emerging anti-counterfeiting materials, persistent luminescence (PersL) materials have attracted much attention owing to their particular luminescent properties, including durable luminescence, facile identification, high security and environment-friendly. Especially, exploiting color-tunable dynamic afterglow materials that facilitate the use of advanced technology such as multi-mode dynamic anti-counterfeiting remains of great realistic significance. Herein, a series of Ba 0.95 Sr 0.05 Ga 2- y Gd y O 4 :Bi 3+ phosphors with tunable photoluminescence and PersL were synthesized by the cationic substitution strategy. The displacement of Ga 3+ by Gd 3+ induces an additional blue emission owing to the generation of a new Bi 3+ luminescence center. The pure white light is realized in Ba 0.942 Sr 0.05 Ga 1.9 Gd 0.1 O 4 :0.8 %Bi 3+ ,0.25 %K + when excited by 325 nm light. Besides, color-tunable emission is triggered by changing the excitation wavelength or temperature. Significantly, excellent room-temperature PersL and dramatically intensified PersL with tunable color output under thermal stimulation are clearly discernible. Such properties result from the existence of multiple Bi 3+ luminescent centers and traps. These findings open up new ideas to produce color-tunable dynamic PersL materials for advanced anti-counterfeiting, information storage and encryption.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jing Li,Yue Li,Wenhua Zhao,Li Liang,Edwin Yue Bun Pun,Hai Lin
Dynamically stimulated color-changing materials provide channels within a multidimensional spatial platform and hold significant potential in the field of information bearing. However, manipulating the photochromic conversion of individual lanthanide emitters and external stimuli to achieve color-switchable emission remains a challenge. Here, multiphonon relaxation between energy levels and cross-relaxation among ions have been manipulated to control the population distribution of different energy levels in Eu 3+ ions doped ultra-low-phonon energy Cs 2 NaYCl 6 (CNYC) crystals, finally achieving full-spectral color switching. Interestingly, the introduction of Tb 3+ , not only enriches the interaction of color information in the spatial dimension, but the water-stimulated phase transition, which triggers the energetic coupling between the Tb 3+ and Eu 3+ ions in the lattice. By controlling the water-soaking time, the reversible change in luminescence color from red-orange to yellow to green have been observed. When these materials encode information, the effectiveness of anti-counterfeiting is verified by demonstrated experiment. In this study, a breakthrough in reversible phase transition of CNYC triggered by water have been observed, and a multidimensional synergistic anti-counterfeiting platform, encompassing spacetime security − photoresponsive channel switching − stimulus remodeling, have been innovatively established. These have promoted the development and improvement of anti-counterfeiting mechanisms.
研究领域:
材料科学
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光学
·
信息加密
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
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IF 3.779
Dandan Ju,Feng Song,Jun Zhang,Chengguo Ming,Feifei Song,Adnan Khan,Aihua Zhou,Xueqin Wang,Lisa Liu
Dynamic tuning upconversion color is the most convenient approach through modulation of pump power density and NIR wavelength for anti-counterfeiting. However, most of bulk upconversion systems suffer from the insensitive response to excitation power and NIR wavelength (980 nm and 1550 nm). Herein, we demonstrate that the excitation power density sensitivity and NIR wavelength sensitivity of bulk microcrystals could be improved via co-doping Li + /Lu 3+ ions. More interestingly, co-doping ions with different valences affect the emission color tendency at 1550 nm excitation, which is contrary to previous reports. The emission color of bulk NaYF 4 :Er/Yb/Li/Lu microcrystals transform from yellow to bright green color through adjusting pump power density and pump wavelength (980 nm and 1550 nm). Moreover, the mechanism of the results has been systematically discussed. The tunable emission colors of bulk NaYF 4 :Er/Yb/Li/Lu microcrystals can be easily distinguished with naked eyes and difficultly counterfeited. Therefore, the upconversion materials have a promising application in transparent anti-fake printing.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Light-Science & Applications
·
2024
·Vol. 13
·期 1
·1-12
·
IF 20.6
Liu Bo-Mei,Lin Yue,Liu Yingchun,Lou Bibo,Ma Chong-Geng,Zhang Hui,Wang Jing
Materials capable of dynamic persistent luminescence (PersL) within the visible spectrum are highly sought after for applications in display, biosensing, and information security. However, PersL materials with eye-detectable and excitation-wavelength-dependent characteristics are rarely achieved. Herein, a nonstoichiometric compound CaGa x O 4 :Bi ( x < 2) is present, which demonstrates ultra-long, color-tunable PersL. The persistent emission wavelength can be tuned by varying the excitation wavelength, enabling dynamic color modulation from the green to the orange region within the visible spectrum. Theoretical calculations, in conjunction with experimental observations, are utilized to elucidate the thermodynamic charge transitions of various defect states, thereby providing insights into the relationship between Bi 3+ emitters, traps, and multicolored PersL. Furthermore, the utility of color-tunable PersL materials and flexible devices is showcased for use in visual sensing of invisible ultraviolet light, multicolor display, information encryption, and anti-counterfeiting. These discoveries create new opportunities to develop smart photoelectric materials with dynamically controlled PersL for various applications.
研究领域:
材料科学
·
信息加密
·
光电材料
✓ 已验证
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2025
·
IF 6.4
W. Y. Li,C. Y. Li,Z. H. Xu,W. B. Dai
Various optical signals are popularly harnessed to realize anticounterfeiting, encryption, and photoluminescence (PL)-based sensing. However, most phosphors can only achieve single PL output under a fixed excitation, thus simultaneous attainment of multimodal PL behaviors remains an imperative pursuit. Herein, a highly integrated multimodal photon-, temperature-, and mechanically responsive Sr2Ga2SiO7:Zn2+/Er3+/Pr3+(SGS:Zn/Er/Pr) is designed/synthesized via a facile solid-state reaction, endowing tunable down/up-converted (DC/UC) PL, mechanoluminescence (ML), and long-persistent PL (LPL) owing to the synergistic effects of self-activated and dopant-induced electronic transitions. serves as both an emitter and a trap center for the self-(L)PL located at ∼468 nm under λex = 267 nm. These behaviors are further optimized by adjusting the content of and by forming a bridge () between trap levels upon Zn2+ incorporation. The excitation and Zn2+ content-dependent PL can be modified from blue to cyan via conflating dual self-PL from the 4T1 → 4A1 transition of Ga3+ at ∼402 nm and . The green DC/red UC PL from Er3+is observed under λex = 357 and 980 nm, respectively. Nonequivalent substitution of Pr3+ at the Sr2+site and the incorporation of Zn2+ can adjust the charge transfer band energy level position and optimize the trap distribution, achieving long-term storage and highly repeatable/efficient LPL/ML generation. Based on abundant PL multimodes, the single-phased SGS:Zn/Er/Pr shows promising applications in sophisticated anticounterfeiting and latent fingerprint detection. Concurrently, owing to the coupled energy levels 2H11/2/4S3/2 of Er3+and the pressure-dependent ML of Pr3+, the SGS:Zn/Er/Pr is also suitably applied as a temperature/stress sensing agent.
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2025
·
IF 4.2
Pengcheng Zhang,Yuanyuan Zhang,Kuo Gao,Diao Zhang,Yu Zhao,Jin Lin,Na Li,Zixuan Shi,Mingxi Zhang,Fengfeng Li
With the growing severity of counterfeiting threats, counterfeiting anti-counterfeiting technologies including fluorescence, QR codes, and query-based labels, rely on static patterns with limited encryption security, leading to inadequate protection and a lack of diversity in anti-counterfeiting strength. Consequently, advancing dynamic anti-counterfeiting systems has become an urgent priority. This study developed a novel dynamic anti-counterfeiting strategy through the synthesis of yellow persistent luminescent CaGa 2 O 4 :Mn 2+ via high-temperature solid-state reaction. In this research, the results demonstrated that at the doping concentration of 0.001 mol Mn, the sample exhibited the best luminescence properties. Furthermore, electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS) analyses revealed that electron traps responsible for the afterglow process primarily originated from oxygen vacancies, and the underlying afterglow mechanism was elucidated. Finally, CaGa 2 O 4 :Mn 2+ long-lasting phosphorescent ink was synthesized and anti-counterfeiting labels were fabricated via screen printing technology. The material's intrinsic photoresponsive behavior enables time-dependent luminance decay post-UV excitation, establishing dynamic authentication through programmable optical evolution, Which effectively realize dynamic anti-counterfeiting.
研究领域:
材料科学
·
光学材料
·
安全技术
·
固态化学
·
纳米技术
✓ 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）