NANOTECHNOLOGY
·
2020
·Vol. 31
·期 36
·365705
·
IF 3.551
Bang Dong,Yongjun Yuan,Mingye Ding,Wangfeng Bai,Shiting Wu,Zhenguo Ji
Fluorescent anti-counterfeiting technique is generally based on the development of luminescent materials, which generally exhibit single-mode emissions under single-wavelength excitation, thus resulting in a poor anti-fake effect. To improve the anti-forgery performance of fluorescent anti-counterfeiting approaches, dual-mode luminescent nanoparticles with the form of a β-NaGdF4:Yb/Ho/Ce@β-NaYF4:Tb/Eu core–shell structure have been skillfully designed and synthesized by a co-precipitation strategy. Through the cross-relaxation process between Ce3+ and Ho3+ ions in the inner core region, the up-conversion luminescence colors of the as-synthesized samples can be turned from green to yellow and finally to red when adjusting the dopant concentration of Ce3+ in the core. By selecting Ce3+ as the sensitizer for harvesting the energy of incident ultraviolet (UV) light and introducing Gd3+ as the ideal intermediate for subsequent energy migration, the down-converting emission colors of the as-obtained samples are also regulated from green to red via a Gd3+-assisted interface energy transfer processes (Ce3+ → Gd3+ → Tb3+, Ce3+ → Gd3+ → Tb3+ → Eu3+). Consequently, dual-mode luminescence with multi-color outputs can be achieved in the pre-designed core–shell nanostructure under the excitation of a 980 nm near-infrared laser and 254 nm UV light. The designed nanoarchitecture with bright dual-mode emissions and tunable colors greatly improves the ability of modern anti-counterfeiting, demonstrating its promising applications in anti-fake and optical multiplexing.
研究领域:
材料科学
·
光学
·
纳米技术
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2024
·Vol. 14
·期 13
·1118
·
IF 4.4
Na Guo,Lili Liu,Guilong Cao,Shurui Xing,Jingying Liang,Jianjun Chen,Zuojun Tan,Yuequn Shang,Hongwei Lei
Lead-free Cs3Cu2I5metal halides have garnered significant attention recently due to their non-toxic properties and deep-blue emission. However, their relatively low photoluminescence quantum efficiency and poor stability have limited their applications. In this work, sodium iodide (NaI) is used to facilitate the synthesis of Cs3Cu2I5nanocrystals (NCs), demonstrating improved photoluminescence intensity, photoluminescence quantum yield, and stability. Systematic optoelectronic characterizations confirm that Na+is successfully incorporated into the Cs3Cu2I5lattice without altering its crystal structure. The improved Photoluminescence Quantum Yield (PLQY) and stability are attributed to the strengthened chemical bonding, which effectively suppresses vacancy defects in the lattice. Additionally, light-emitting diodes (LEDs) based on 10% NaI-doped Cs3Cu2I5NCs were assembled, emitting vibrant blue light with a maximum radiant intensity of 82 lux and Commission Internationale de l’Eclairage (CIE) chromaticity coordinates of (0.15, 0.1). This work opens new possibilities for commercial lighting display applications.
研究领域:
材料科学
·
光电技术
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Qin Liu,Peipei Dang,Guodong Zhang,Hongzhou Lian,Ziyong Cheng,Guogang Li,Jun Lin
Mn2+-doped luminescent materials play a significant role in a variety of fields, including modern lighting, displays, and imaging. Mn2+ exhibits a broad and adjustable emission, hinging on the local environment of the crystal field and the interaction of the 3d5 electrons. However, it is still a challenge to realize the precise control of the emission of Mn2+ ions due to site-prior occupation in a specific lattice. Here, the formation of Mn–Mn dimers is proposed to be an effective strategy to design a novel red emission. Multimode emitters in Mn2+-activated AZn4(PO4)3 (A = K, Rb, and Cs) with unique [Zn4PO12] chains and [ZnOn] groups are observed to achieve regular green and unusual red emissions. KZn4(PO4)3:Mn2+ shows broad dual emissions at 542 and 608 nm, attributed to [MnO4] and [Mn2O7] dimers, respectively. While K is replaced with Rb and Cs, the Zn ions form [ZnO4] tetrahedra and [ZnO5] octahedra. RbZn4(PO4)3:Mn2+ exhibits a broad red emission at 618 nm, ascribing to [Mn2O7] and [Mn2O8] dimers. CsZn4(PO4)3:Mn2+ also displays a broad orange-red emission at 608–620 nm with increasing doping levels, deriving from energy transfer from [MnO5] to [Mn2O7] and [Mn2O8] dimers. This work provides a framework for creating novel red emissions from Mn2+-doped luminescent materials.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SYNTHETIC METALS
·
2015
·
IF 2.252
Tianzhi Yu,Lijing Ma,Shupei Yu,Zixuan Xu,Yuling Zhao,Hui Zhang
Two new iridium(III) complexes containing the coumarin derivatives as cyclometalated ligands (L) and the carrier transporting group-functionalized dibenzoylmethane as ancillary ligands have been successfully synthesized and characterized. The X-ray crystal structure analyses of the free ligands and the complex containing a carbazole-functionalized dibenzoylmethane as ancillary ligand were described. The photophysical properties of the Ir(III) complexes were examined via ultraviolet-visible, photoluminescence spectroscopic spectra. The good thermal stability of the Ir(III) complexes was demonstrated by the thermogravimetric analysis. The doped light-emitting devices using the Ir(III) complexes as dopants were fabricated. The devices based on the complex containing a carbazole-functionalized dibenzoylmethane as ancillary ligand possess better performance as compared with the devices fabricated by the complex containing a 1,3,4-oxadiazole-functionalized dibenzoylmethane as ancillary ligand. The devices based on the former Ir(III) complex with a 15 wt% doping concentration exhibit a maximum efficiency of 13.8 cd/A and a maximum brightness of 4955.7 cd/m 2 .
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2021
·Vol. 9
·期 46
·16634-16644
·
IF 7.393
Dangli Gao,Jie Gao,Feng Gao,Qingqing Kuang,Yong Pan,Yafei Chen,Zhengwei Pan
Traditional luminescent inks used in anti-counterfeiting applications usually consist of single-mode photoluminescence (PL) or up-conversion luminescence (UCL) materials, which are mainly operated in single-level, monochromatic anti-counterfeiting and can be easily counterfeited. Here we report the achievement of quintuple-mode, multi-colour dynamic anti-counterfeiting using multi-mode Zn3Ga2GeO8:Cr3+,Yb3+,Er3+ and Zn1.6Li0.4GeO4:Mn2+ persistent phosphors as the luminescent inks. The Zn3Ga2GeO8:Cr3+,Yb3+,Er3+ phosphors exhibit quintuple luminescence modes of PL, persistent luminescence (PersL), photostimulated luminescence (PSL), photostimulated persistent luminescence (PSPL) and UCL with rich emission colours, while the Zn1.6Li0.4GeO4:Mn2+ phosphors possess quadruple luminescence modes of PL, PersL, PSL and PSPL with a long perceptible green afterglow. A ‘dragonfly-on-lotus’ pattern printed using these multi-mode persistent phosphors shows dynamic evolution of emission colours and brightness under different luminescence modes. The design strategy reported in this study may lead to the design and development of more sophisticated optical anti-counterfeiting technology.
研究领域:
材料科学
·
光学
·
防伪技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Yi Zhang,Xihui Shan,Xulong Lv,Dongxun Chen,Shihai Miao,Weili Wang,Yanjie Liang
Discovering multimodal luminescent materials capable of being excited by diverse excitation sources and producing different wavelengths of light emission in a single material system remains a long-standing challenge. Herein, a Pr 3+ single-doped Li 2 CaSiO 4 phosphor is reported as an efficient multimodal luminescence material, which responds to convenient light sources including X-ray tube, 450 nm blue LED/laser, and white LED. Upon X-ray excitation, intense long-lasting red (>24 h) and ultraviolet-C (UVC, >12 h) persistent luminescence can be detected simultaneously, enabling a self-sustained glowing material suitable for working in both dark and bright environments. Significant enhancement of UVC afterglow is observed under the continuous photostimulation of white LED. Moreover, under the excitation of blue light, UVC upconversion luminescence is realized with the aid of unique energy levels of the Pr 3+ emitter. Besides, this material also exhibits exceptional white-to-brown photochromism performance in bright fields only in response to X-ray irradiation, accompanied by excellent bleaching and recovery capability upon thermal or blue light stimulation. The combination of persistent luminescence, photo-stimulated luminescence, upconversion luminescence and photochromism in this integrated multimodal luminescent Li 2 CaSiO 4 :Pr 3+ phosphor provides new and exciting directional solutions for multifunctional applications such as optical information storage and anti-counterfeiting.
研究领域:
材料科学
·
光学工程
·
信息存储技术
·
防伪技术
✓ 已验证
产品关联
DOI
高影响因子
Applied Sciences-Basel
·
2015
·Vol. 5
·期 4
·1494-1502
·
IF 1.484
Wangqing Shen,Yiwen Zhu,Zhengling Wang
Sr4Si3O8Cl4co-doped with Eu2+, Bi3+were prepared by the high temperature reaction. The structure and luminescent properties of Sr4Si3O8Cl4:Eu2+, Bi3+were investigated. With the introduction of Bi3+, luminescent properties of these phosphors have been optimized. Compared with Sr3.90Si3O8Cl4:0.10Eu2+, the blue-green phosphor Sr3.50Si3O8Cl4:0.10Eu2+, 0.40Bi3+shows stronger blue-green emission with broader excitation in near-UV range. Bright blue-green light from the LED means this phosphor can be observed by the naked eye. Hence, it may have an application in near UV LED chips.Keywords:luminescent properties;phosphors;light-emitting diodes;Sr4Si3O8Cl4
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
COLORATION TECHNOLOGY
·
2015
·Vol. 131
·期 3
·206-212
·
IF 1.262
Zhi-Yong Chen,Yan-Fang Ma,Ya-Ling Liu,Yi-Feng Sun,Zhen-Guo Chi
Three novel tetraphenylethene–organophosphorus dyads – (6-oxido-6 H -dibenz[c,e][1,2]oxaphosphorin-6-yl)[4-(1,2,2-triphenylvinyl)phenyl] methanol, diphenyl {hydroxy[4-(1,2,2-triphenylvinyl)phenyl]methyl} phosphine oxide, and di(3,5-dimethylphenyl){hydroxy[4-(1,2,2-triphenylvinyl)phenyl] methyl} phosphine oxide – were synthesised and characterised by 1 H, 13 C, and 31 P nuclear magnetic resonance spectroscopy, mass spectrometry, and elemental analysis. The photoluminescence properties were studied. All three dyads exhibited intense solid-state blue emission peaking at 449–466 nm, and also displayed aggregation-induced emission behaviours. The emission decays of these dyads in the solid state also fitted well with a triexponential model with an average lifetime of 2.65–4.42 ns. The experimental results demonstrated that the luminescent properties are highly dependent on the nature of the organophosphorus groups. The choice of phosphorus-containing components can cause variations in the photoluminescence emission and photoluminescence decays.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
OPTIK
·
2022
·
IF 2.84
Taotao Zhang,Rui Xu,Hang Lv,Zhenxiang Wang,Haidong Ye,Haiqin Liu,Liang Chen
The light-emitting electrochemical cells (LECs) have received extensive attention from researchers in recent years due to their simple single-layer structure, air-stable metal electrodes, and low manufacturing cost. So far, reports on the use of LEC active layer emitter materials have mainly focused on ionic transition metal complexes (iTMCs) and conjugated polymers (CPs). The application of the above materials in blue LECs is restricted due to high cost, complicated synthesis process, and poor stability, which results in the slow development of blue LECs. A novel blue LECs device based on aggregation-induced emission (AIE) small molecule (2,3-diphenylbenzo[ b ]thiophene S, S-sulfur dioxide, DP-BTO) with a peak luminance of 36.58 cd/m 2 , a CEmax of 1.14 cd/A, and an EQEmax of 0.46% was reported in this work. The blue light emission centered at ~460 nm was exhibited at a voltage above 6 V. This work successfully constructed blue light-emitting LECs devices based on AIE materials, opening up a new research avenue for the application of AIE materials in the field of thin-film device development.
研究领域:
材料科学
·
光电技术
·
有机电子学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2021
·Vol. 32
·期 6
·7026-7033
·
IF 2.478
Shen Menghan,Cheng Zhiyuan,Li Yongjin,Liu Tong,Peng Yan,Zhang Yueli
The single-band red upconversion (UC) emission of lanthanide-doped materials have attracted attention due to its great potential for versatile applications. In this work, YbOCl: x Er 3+ with super pure red UC emission had been successfully synthesized by conventional high temperature solid-state reaction. X-ray powder diffraction (XRD) confirmed the rhombohedral structure with space group R -3 m (166). Scanning electron microscopy (SEM) exhibited agglomeration morphology of smooth sheets with nanometer thickness. The UC emission spectra of YbOCl:Er 3+ manifested intense red emission and much lower green emission when pumped by 980 nm diode laser. The dominating red emission peaking at 670 nm was assigned to the electron transition 4 F 9/2 → 4 I 15/2 . The green emission at 521 nm and 547 nm were corresponding to 2 H 11/2 → 4 I 15/2 and 4 S 3/2 → 4 I 15/2 transition of Er 3+ , respectively. The CIE chromaticity coordinates showed the color of samples lain in red region and the purity of red emission could be tuned by the concentration of Er 3+ . The UC luminescence mechanism was proposed based on the relationship of UC intensity versus pump power density and their lifetime. Our research provided a new thought for realizing single-band red emission without any further modification.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
CRYSTAL GROWTH & DESIGN
·
2022
·
IF 4.01
Zeyu Cheng,Hao Ren,Yazhao Wang,Shengdi Ta,Peng Zhang,Yuhua Yang,Shoulei Xu,Bernard Albert Goodman,Wen Deng
Large-size and high-quality stable ZrO2 single crystals containing x mol % Yb2O3 (x = 7, 8, 9, 10) (denoted as xYbSZ), and 8YbSZ crystals doped with 0.5 mol % Er2O3 were grown by the optical floating zone (OFZ) method. Yb3+ was indicated by XRD and Raman spectroscopy to have successfully entered into the ZrO2 lattice, which was stabilized in the cubic phase when the concentration of Yb2O3 was ≥8 mol %. Er3+ successfully entered the 8YbSZ lattice, and its spectral absorption intensity was enhanced compared to Er3+ in the corresponding yttria-stabilized zirconia (8YSZ), thus demonstrating that the Yb3+ ion has an excellent sensitizing effect on the up-conversion luminescence of Er3+. Fluorescence decay curves show that the up-conversion luminescence excited state lifetime of Er3+ is significantly enhanced in 8YbSZ compared to 8YSZ. Thus, these results demonstrate that Yb3+ ions not only successfully stabilize ZrO2 in the cubic phase structure but also maintain their role as an up-conversion luminescence sensitizer for Er3+ ions.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
ORGANIC ELECTRONICS
·
2018
·
IF 3.68
Yan Meng,Mahshid Ahmadi,Xiaoyan Wu,Tianfei Xu,Long Xu,Zuhong Xiong,Ping Chen
Compared to organic-inorganic halide perovskites ( e.g. , MAPbBr 3 and FAPbBr 3 ), all-inorganic CsPbBr 3 perovskite has shown to be a more promising candidate for application in light-emitting diodes (LEDs) due to higher photoluminescence quantum efficiency and thermal stability. Yet, the external quantum efficiency (EQE) of polycrystalline (3D) CsPbBr 3 based PeLEDs needs further improvement. The low efficiency was attributed to severe luminescence quenching at PEDOT:PSS (Poly-(3,4-ethylenedioxythiophene):poly(styrenesulfonate))/CsPbBr 3 interface arising from (i) interfacial energy barrier between PEDOT:PSS and CsPbBr 3 layer, (ii) poor crystallization and large pinholes in perovskite film, and (iii) indium tin oxide (ITO) anode etching due to PEDOT:PSS acidity. Therefore, it is necessary to address all these problems simultaneously to reduce the luminescence quenching and to improve device efficiency. Here, we introduce a feasible approach to modify the PEDOT:PSS layer in order to reduce the luminescence quenching at PEDOT:PSS/CsPbBr 3 interface. In this modification, PEDOT:PSS is mixed with a MoO 3 ammonia solution at desired volume ratios. Our studies demonstrate that upon this treatment, not only hole injection and crystallization of perovskite film are improved but also ITO is protected from etching by the acidic nature of PEDOT:PSS. This modification result in a high performance all inorganic CsPbBr 3 LED with a maximum luminance of ∼34420 cd/m 2 and a current efficiency of ∼7.30 cd/A. In addition, our state-of-the-art perovskite LEDs (PeLEDs) exhibit no degradation after 2 h of continuous operation, representing a stable PeLEDs based on one-step solution processed polycrystalline CsPbBr 3 .
研究领域:
材料科学
·
光电子学
✓ 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）