CHEMISTRY OF MATERIALS
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2024
·
IF 7.2
Hongwei Zheng,Xiaoming Wang,Zhuo Li,Tianhui Liu,Hui Fu,Hu Zhang,Zupei Yang,Huan Jiao
The exploration of new luminescent materials is driven by potential applications in solid-state lighting and display technologies. In this paper, we employed an anionic condensation approach to craft novel oxonitridosilicate compounds by substituting 3O2– with 2N3– in a carefully selected system. This approach enabled us to synthesize a highly condensed oxonitridosilicate compound LaSr4Si5N9O2, which crystallizes in the orthorhombic crystal system with the space group Ama2 (no. 40) and lattice parameters a = 9.2986(1) Å, b = 23.4382(1) Å, c = 5.371(1) Å, V = 1170.55(1) Å3, and Z = 4. The condensation appears inside the layer, with dreier rings originating from neighboring tetrahedra connected by bridging nitride (N[2]). This enriches the possibility of using the approach to design multiple layered or other featured oxonitridosilicates. Furthermore, we investigated the luminescence properties when doped with rare-earth ions. The Pr3+-doped LaSr4Si5N9O2 exhibits a remarkably narrow-band red emission (λem ≈ 618 nm, fwhm ≈ 54 nm) when excited by UV and blue light.
研究领域:
材料科学
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固态照明
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显示技术
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
·
IF 5.8
Juyu Yang,Haojun Yu,Yan-gai Liu,Ruiyu Mi,Ci-an Xie,Linlin Wang,Tonglu Sun,Jingang Liu,Lefu Mei
Currently, the application potential of Cr 3+ doped near-infrared (NIR) fluoride phosphors excited by blue light is promising. However, the development of near-infrared fluoride phosphors with wider emission bandwidth remains a challenge. Herein, we employed the hydrothermal method to prepare K 2 NaCrF 6 :Fe 3+ phosphors. Upon excitation at 432 nm, the K 2 NaCrF 6 :xFe 3+ phosphors exhibited broad near-infrared emission, with the main peak ranging from 752 nm to 780 nm. As the Fe 3+ concentration increased, the luminescence intensity of the K 2 NaCrF 6 :xFe 3+ phosphor decreased, accompanied by a redshift in the emission band and an increase in the full width of the emission spectrum half-peak. These changes can be attributed to the dipole-dipole interaction, specifically the energy transfer between Fe 3+ and Cr 3+ , leading to the 4 T 2 ( 4 F) → 4 A 2 (Cr 3+ ) and 4 T 1 ( 4 G) → 6 A 1 ( 6 S) (Fe 3+ ) transitions.
研究领域:
材料科学
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光学
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光子学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
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IF 4.527
Yue Su,Lifang Yuan,Hai Liu,Guangting Xiong,Haoyi Wu,Yihua Hu,Xuxin Cheng,Yahong Jin
The near-infrared (NIR) light source has a huge potential for foodstuff analysis, biometric identification, physiological monitoring, and night vision technology with real-time and non-destructive advantages. Demand-led growth impels the exploration of novel NIR phosphors with broadband emission. Here we report a new kind of blue-light excitable NIR phosphor Mg 7 Ga 2 GeO 12 : xCr 3+ , in which the multi-site occupation of Cr 3+ induces broadband NIR emission in the range of 600–1200 nm with a large full width at half maximum (FWHM) of ~190 nm and a NIR photoluminescence quantum yield (PLQY) of 12.06% at x = 0.02. The FWHM can be effectively adjusted from 101 to 226 nm via multisite occupancy preference of Cr 3+ ions. The PL intensity remains ~50% and nearly 100% of the initial level after heated up to 400 K and immersed in hot water (100 °C) for 24 h, respectively, demonstrating good thermal stability and robust chemical stability. The broadband emission originated from multi-site PL centers of Cr 3+ is discussed in detail by the temperature-dependent PL behaviors and PL decay lifetime. Finally, a broadband emission NIR-LED is fabricated, based on which a proof-of-concept application for night vision is demonstrated. This work not only provides a strategy for the design and developing of novel broadband NIR phosphors, but also indicates the potential for various advanced spectroscopy applications.
研究领域:
材料科学
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光学
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光子学
✓ 已验证
DOI
高影响因子
Laser & Photonics Reviews
·
2024
·Vol. 18
·期 11
·2400447
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IF 9.8
Fangyi Zhao,Yuhe Shao,Quanlin Liu,Jiasong Zhong
Near-infrared (NIR) phosphor-converted light-emitting diode (pc-LED) light sources in the second NIR window (NIR-II, 1000–1700 nm) have sparked great interest for their emerging applications in non-destructive detection and medical diagnostics fields. However, the development of efficient NIR-II phosphors that can be excited by commercial blue LED chips remains a significant challenge, and thus impeding the applications of NIR pc-LED. Herein, a blue-light-excitable broadband NIR-II luminescence of Ni 2+ is achieved upon incorporating Cr 3+ and Ni 2+ into the Ca 3 Ga 2 Ge 3 O 12 (CGGO) host simultaneously. Through the energy transfer from Cr 3+ to Ni 2+ , CGGO:Cr 3+ ,Ni 2+ phosphor presents the improved NIR-II emission peaking at 1470 nm under 460 nm blue light excitation. The internal/external quantum efficiency values are significantly improved from 13.8%/3.3% to 24.6%/13.3% along with the enhanced luminescence thermal stability. Finally, a NIR pc-LED is fabricated by combining CGGO:Cr 3+ ,Ni 2+ phosphor with 450 nm blue chip, and its potential applications in non-destructive examination and biomedical imaging fields have been demonstrated. The strategy of Cr 3+ and Ni 2+ co-doping solves the problem that Ni 2+ luminescence cannot be effectively excited by blue light and provides the design insights to exploit more ultra-broadband NIR pc-LEDs based on blue LED chips.
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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非侵入性检测
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分子影像学
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2022
·Vol. 10
·期 12
·2102619
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IF 10.05
Binbin Su,Jiance Jin,Yinhui Peng,Maxim S. Molokeev,Xiaobao Yang,Zhiguo Xia
The discovery of rare-earth free luminescent materials with blue-light-excitable characteristic is of great importance for solid-sate lighting applications. Herein, a Cu(I)-based 0D luminescent hybrid ( 1,3-dppH 2 ) 2 Cu 4 I 8 ∙H 2 O is synthesized by a facile solution method, and it shows the orange-red emission peaking at 625 nm upon 460 nm excitation. The structure-related luminescence mechanism has been elaborated by experimental and theoretical investigations. Moreover, the emission intensity remains unchanged even after continuous water treatment for 60 days due to the improved structural stability originating from intermolecular π–π interaction between organic cations. A warm white light-emitting diode (LED) device with the color rendering index of 91.4% has been fabricated by combining the 440 nm LED chip, green-emitting Lu 3 Al 5 O 12 :Ce 3+ , and ( 1,3-dppH 2 ) 2 Cu 4 I 8 ∙H 2 O. This work provides a new design route towards 0D cuprous halide materials and will initiate more exploration of their intrinsic luminescence mechanism.
研究领域:
材料科学
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光电
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固态照明
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
·
IF 13.273
Shuai Zhang,Yifei Zhao,Jiadong Zhou,Hong Ming,Chun-Hai Wang,Xiping Jing,Shi Ye,Qinyuan Zhang
Manganese (II) compounds are promising luminescent candidates for white light-emitting diodes (WLEDs) applications. However, the forbidden d - d transition of Mn 2+ ion makes the absorption of blue light and emission relatively weak without a sensitizer. The strategy of isolating MnX n (X is the ligand) with some ionic liquids is used to design two new hybrid compounds in this study, focusing on the orbital hybridization to relax the parity selection rule of the d - d transition. A large hindrance of the organic cations in the two new Manganese (II) hybrids enables a large Mn-Mn distance (up to ~ 10 Å) to form zero-dimensional (0D) structures, and the Mn sites in both compounds have a low site symmetry ( C 2 or C 1 ). The 0D structure of MnX n polyhedral is beneficial to isolatedly investigate the orbital hybridization of the ligand and Mn 2+ ion. A higher orbital hybridization extent for Mn-Br bond is evidenced by Density Functional Theory (DFT) simulation. This conclusion leads to the strong and stable green light emissions under preferable blue light (460 nm) excitations, giving photoluminescence quantum yields (PLQYs) as high as 76%. The WLEDs fabricated with these compounds have presented high luminous efficiency up to ~130 lm/W and survived multiple stability tests. The research favors the discovery of ideal Mn compounds for displays and lighting applications.
研究领域:
材料科学
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光电
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光子学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2019
·Vol. 48
·期 31
·11791-11802
·
IF 4.052
Baochen Wang,Ruiyu Mi,Yangai Liu,Ming Yu,Zhaohui Huang,Minghao Fang
The luminescence spectra of some trivalent rare-earth ions in a garnet host present interesting multisite structures; however, their mechanism is still not fully understood. In this study, for the first time, we directly observed two luminescence centers of Ce3+ at a single site in a novel garnet Ca3Sc2Ge3O12 phosphor. The spectral characteristics of the two luminescence centers were clearly identified using site-selective and time-resolved spectroscopy. Luminescence excitation was observed at 425 nm and 450 nm, corresponding to emissions at 490 (Ce(I)) nm and 530 (Ce(II)) nm. The decay curves confirmed the existence of energy transfer from Ce(I) to Ce(II). The potential mechanisms of the multisite luminescence are also discussed. This study gives a new insight into the concentration-dependent red-shift and inhomogeneous broadening of the Ce3+ emission band in the garnet phosphor. The title phosphor showed excellent thermal stability, with more than 90% of the initial intensity at the functioning temperature (323 K). Finally, a white LED lamp was fabricated, which exhibited an excellent color rendering index (82.3) and a proper correlated color temperature (3582 K). These results demonstrate that Ca3Sc2Ge3O12:Ce3+ is highly promising to serve as a blue-pumped phosphor for white LEDs.
研究领域:
材料科学
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光电技术
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光子学
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
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2018
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IF 2.32
Hong Ming,Junfei Zhang,Shuifu Liu,Jiaqing Peng,Fu Du,Jianhui Huang,Libin Xia,Xinyu Ye
Lack of red-light of current w-LEDs restricts their applications in the field of high color rendering index warm solid-state lighting. Fluoride phosphors doped with Mn 4+ provide an efficient way to resolve the problem. Unfortunately, these excellent Mn 4+ activated fluoride red phosphors are generally synthesized in highly toxic HF solution. In this paper, we report a novel green synthetic route to prepare a non-rare-earth and nonequivalent doping type of K 2 NbF 7 :Mn 4+ red phosphor with micro-rod-like morphology. The results of XRD and its Rietveld refinement reveal that all the samples possessed only a single phase with monoclinic P21/c structure and the Mn 4+ ions were successfully incorporated into the crystal lattice . The Mn 4+ ions in K 2 NbF 7 matrix have a highly distorted octahedral environment, which strengthen the intensity of zero phonon line (ZPL). The strongest absorption and excitation bands appear in blue region of diffuse refection spectra (DRS) and the photoluminescence excitation (PLE) of K 2 NbF 7 :Mn 4+ sample, which demonstrates the product perfectly match with the most popular GaN-based blue chip. Under blue light illumination, the as-prepared K 2 NbF 7 :Mn 4+ sample exhibits intense sharp-line red fluorescence (∼628 nm) with internal quantum yield (QY) of 71.3%, an extreme narrow full width at half-maximum (FWHM) of ∼2.8 nm, and an ultra-high-color purity of 99.2%. Impressively, by incorporating K 2 NbF 7 :Mn 4+ as a red component, a warm w-LED with high CRI of 83.8, low color temperature of 3010 K and high luminous efficiency of 115.91 lm/W is obtained, demonstrating great validity of K 2 NbF 7 :Mn 4+ red phosphor for white LED devices.
研究领域:
材料科学
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光电技术
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照明技术
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Daqin Chen,Gaoliang Fang,Xiao Chen
Tunability of emitting colors of perovskite quantum dots (PQDs) was generally realized via composition/size modulation. Due to their bandgap absorption and ionic crystal features, the mixing of multiple PQDs inevitably suffers from reabsorption and anion-exchange effects. Herein, we address these issues with high-content Mn2+-doped CsPbCl3 PQDs that can yield blue-excitable orange Mn2+ emission benefited from exciton-to-Mn energy transfer and Cl-to-Br anion exchange. Silica-coating was applied to improve air stability of PQDs, suppress the loss of Mn2+, and avoid anion-exchange between different PQDs. As a direct benefit of intense multicolor emissions from Mn2+-doped PQD@SiO2 solid phosphors, a prototype white light-emitting diode with excellent optical performance and superior light stability was constructed using green CsPbBr3@SiO2 and orange Mn: CsPb(Cl/Br)3@SiO2 composites as color converters, verifying their potential applications in the field of optoelectronics.
研究领域:
材料科学
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光电技术
·
纳米技术
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光子学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Yue Su,Lifang Yuan,Bo Wang,Sijian Wu,Yahong Jin
Metal halide perovskites (MHPs) have sparked ongoing research interest due to their high-performance optoelectronic properties. However, blue-light excitable near-infrared (NIR) emitting MHPs is still inaccessible and the achievement of robust thermal-quenching resistance so far remains a huge challenge. In this work, we report on the synthesis of lead-free all-inorganic Mn 2+ -based perovskite-like single crystals using the designed nonstoichiometric precursor ratio. The special crystal structure endows Mn 2+ with efficient blue light excitation and red emission, which enables the capabilities of a good matching with commercial blue LED chips and an efficient sensitization for Ln 3+ emitters. The incorporations of Yb 3+ , Er 3+ , and Ho 3+ functionalize the CsMnCl 3 single crystals with multiple NIR emissions by virtue of feeding the energy from Mn 2+ to Ln 3+ via multi-channels. Most remarkable is the achievement of the robust thermal-quenching resistance, exhibiting (near-) zero-thermal-quenching and even anti-thermal quenching, of the Ln 3+ NIR emissions above room temperature . Finally, as a proof-of-concept study, a prototype of an NIR-LED device was fabricated. This work not only provides a general strategy to unlock the blue-light excitable NIR emission from f-f transitions of Ln 3+ ions, and a fundamental understanding of the sensitization-activation mechanisms in Ln 3+ -functionalized manganese (Ⅱ)-based perovskite-like phosphor, but also endows the MHPs with optical functionalities for the future high-potential applications, such as NIR phosphor-converted LEDs, and optical telecommunication.
研究领域:
材料科学
·
光电学
·
光子学
·
固体物理
·
无机化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）