Science Advances
·
2019
·Vol. 5
·期 1
·
IF 12.804
Ming Zhao,Zhiguo Xia,Xiaoxiao Huang,Lixin Ning,Romain Gautier,Maxim S. Molokeev,Yayun Zhou,Yu-Chun Chuang,Qinyuan Zhang,Quanlin Liu,Kenneth R. Poeppelmeier
Solid-state phosphor-converted white light-emitting diodes (pc-WLEDs) are currently revolutionizing the lighting industry. To advance the technology, phosphors with high efficiency, tunable photoluminescence, and high thermal stability are required. Here, we demonstrate that a simple lithium incorporation in NaAlSiO4:Eu system enables the simultaneous fulfillment of the three criteria. The Li substitution at Al sites beside Na sites in NaAlSiO4:Eu leads to an enhanced emission intensity/efficiency owing to an effective Eu3+ to Eu2+ reduction, an emission color tuning from yellow to green by tuning the occupation of different Eu sites, and an improvement of luminescence thermal stability as a result of the interplay with Li-related defects. A pc-WLED using the Li-codoped NaAlSiO4:Eu as a green component exhibits improved performance. The phosphors with multiple activator sites can facilitate the positive synergistic effect on luminescence properties.
研究领域:
材料科学
·
光电子学
·
固态照明
·
无机化学
·
发光学
✓ 已验证
DOI
高影响因子
CHROMATOGRAPHIA
·
2012
·Vol. 75
·期 21
·1287-1293
·
IF 1.195
Wang Shuping,Li Xinchun,Yang Jianping,Yang Xiujuan,Hou Fenghua,Chen Zuanguang
In clinical medicine, urine creatinine concentration is an important marker in the evaluation of renal function and muscular dysfunctions. Herein, we reported a novel method for rapid determination of creatinine in urine by microchip electrophoresis with light-emitting diode induced fluorescence detection. Creatinine was derivatized by fluorescein isothiocyanate, and then quantitatively detected by the developed microchip LED induced fluorescence detection system. The excitation and emission wavelengths were 490 and 523 nm, respectively. The urine samples were analyzed after centrifuge and filtration. A baseline separation was obtained in <30 s using 10 mM borate buffer (pH 9.0, containing 45 mM sodium dodecylsulfate), with separation voltage of 1.5 kV. Good linearity was obtained ( r
2 = 0.9978) in the concentration range of 10.0–2.00 × 10 3 μM, and the limit of detection was 2.87 μM ( S/N = 3). The recovery was 96.0–107 %, and the interday precision was <4.5 % ( n = 6). To validate assay results, we compared the present method with the Jaffe’s colorimetric assay by measuring real urine samples. The method was reliable, sensitive, high-speed, low-cost and suitable for the routine analysis of creatinine in biofluids.
研究领域:
临床医学
·
分析化学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Chemistry
·
2021
·
IF 8.301
Nan Ma,Wei Li,Balaji Devakumar,Zongjie Zhang,Xiaoyong Huang
The development of high-brightness far-red-emitting phosphors with emission wavelength within 650–750 nm is of great significance for indoor plant cultivation light-emitting diode (LED) lighting. Herein, we demonstrate a novel efficient far-red-emitting phosphors CaMg 2 La 2 W 2 O 12 :Mn 4+ (abbreviated as CMLW:Mn 4+ ) toward application in plant cultivation LEDs. Interestingly, the CMLW:Mn 4+ phosphors show a broad excitation band in the 250–600 nm spectral range with two peaks at 352 and 479 nm, indicating they could be efficiently excited by near-ultraviolet and blue light. Under 352 nm excitation, the CMLW:Mn 4+ phosphors exhibit an intense far-red emission band in the wavelength range of 650–800 nm peaking at 708 nm, corresponding to the 2 E g → 4 A 2g transition of Mn 4+ ions. Mn 4+ doping concentration-dependent luminescence properties are studied in detail, and the concentration quenching mechanism is also investigated. Particularly, the internal quantum efficiency of CMLW:Mn 4+ phosphors reaches as high as 44%, and their PL spectra match well with the absorption spectrum of phytochrome P FR (P FR stands for far-red-absorbing form of phytochrome). Furthermore, a prototype LED device is fabricated by coating the as-prepared CMLW:0.8%Mn 4+ phosphors on a 460 nm blue LED chip, which produces bright far-red emissions upon 20–300 mA driving currents. This work reveals that the newly discovered far-red-emitting CMLW:Mn 4+ phosphors hold great potential for application in indoor plant cultivation.
研究领域:
材料科学
·
植物学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
·
2018
·Vol. 33
·期 7
·1217-1223
·
IF 3.608
Zhirong Zou,Fujian Xu,Yunfei Tian,Xiaoming Jiang,Xiandeng Hou
A miniaturized UV-LED photochemical reactor is proposed for selenium photochemical vapor generation (Photo-CVG). The miniaturized Photo-CVG reactor with a coin size mainly consists of an ultraviolet light-emitting-diode (UV-LED) and a quartz coil with nano-TiO2 coating on its inner wall. It was coupled with an atomic fluorescence spectrometer (AFS) as a sample introduction device for trace selenium determination. The nano-TiO2 coating process, UV-LED wavelength and correlative experimental parameters as well as potential interference were investigated in detail. Under optimized experimental conditions, limits of detection of 0.21 and 0.28 μg L−1 for Se(VI) and Se(IV) were obtained, respectively, with a relative standard deviation (n = 3) of 2.5% and 1.0% at 20 μg L−1. The potential application of this UV-LED Photo-CVG AFS was demonstrated by successfully analyzing a certified reference water sample and several mineral water samples.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 81
·51512-51520
·
IF 3.108
Minmin Liu,Lin Zhang,Bei-dou Xi,Shuili Yu,Xiaojun Hu,Li-an Hou
The activation of persulfate (PS) by metal catalysts under visible light is expected to offer a promising oxidation reaction for the removal of contaminants from water. Herein, we investigated activated PS systems under visible light irradiation for the generation of reductive species to decompose ciprofloxacin (CIP). Improved PS activation using TiO2/Fe2O3/zeolite ((n)TiFeZ) under visible light irradiation favorably leads the reaction to generate reductive radicals. The enhanced degradation efficiencies of the (n)TiFeZ–PS system for CIP removal was due to the extended absorbance in the visible-light region and improved space separation of photo-induced charge carriers. The (4)TiFeZ catalyst exhibited better performance for CIP removal as compared to the other samples. The CIP was completely degraded in 120 min using 1 g L−1 (4)TiFeZ and 5.0 mM PS at pH 7.0. The characterization and electron paramagnetic resonance (EPR) of (n)TiFeZ suggested that CIP was mainly degraded by surface-adsorbed radicals generated from the reaction between PS and Fe(II) on the samples under visible light. The reductive systems coupled with (n)TiFeZ exhibited high CIP degradation efficiency and high potential for the decomposition of other antibiotic compounds.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Zhaoming Wang,Zixian Wei,Yuting Cai,Lei Wang,Mutong Li,Ping Liu,Rongjun Xie,Lai Wang,Guodan Wei,H. Y. Fu
Cesium lead halide perovskite nanocrystals have recently become emerging materials for color conversion in visible light communication (VLC) and solid-state lighting (SSL), due to their fast response and desirable optical properties. Herein, perovskite nanocrystal-polymethyl methacrylate (PNC-PMMA) films with red and yellow emission are prepared. The PNC-PMMA films, with optical properties such as a short lifetime and air stability, are used to make broadband color converters based on a high-bandwidth 75 μm blue micro-LED (μLED) for VLC. The yellow-emitting CsPb(Br/I)3 PNC-PMMA has a high bandwidth of 347 MHz, while the red-emitting CsPbI3 PNC-PMMA exhibits a higher modulation bandwidth of 822 MHz, which is ∼65 times larger than that of conventional phosphors. After fixing the two PNC-PMMA films in front of the μLED, a qualified warm white light is generated with a correlated color temperature of 5670 K, a color rendering index of 75.7, and a de L’Eclairage (CIE) coordinate at (0.33, 0.35). Although the color conversion of the blue light sacrifices some received power and slightly reduces the overall bandwidth from 1.130 to 1.005 GHz, a maximum real-time data rate of 1.7 Gbps is still achievable using the non-return-to-zero on–off keying modulation scheme, which is ∼6 times higher than that of the previous record. This study provides a practical approach to develop a considerably high-bandwidth white-light system for both high-speed VLC and high-quality SSL.
研究领域:
材料科学
·
光电
·
通信工程
·
光子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2023
·
IF 3.9
Ji'an Song,Yan Gao,Zhichao Meng,Zelong Jiang,Xiaobing Cao,Qingguang Zeng,Tao Hu
All-inorganic metal halide perovskites have attracted extensively attentions because of superior optoelectronic properties. Presently, tremendous progress is reached in green and red emitting perovskites , while the explorations of blue emitting perovskites are lag behind, and it also faces low emission efficiency and long-term stability issues. In this work, nickel-bromide passivation strategy was proposed to improve optical properties and chemical stability of blue emitting CsPbBr 3 nanoplatelets (NPLs) with strong quantum-confinement effects. As a result of the repaired Br − vacancy on the surface of the NPLs and enhanced structural stability of CsPbBr 3 lattice by Ni 2+ doping, the emission efficiency of the NPLs is increased from 33.2% to 78%, and it can be stored up to 30 days without significant PL loss. Benefiting from the excellent overall performance, a liquid-type monochrome LED device fabricated by using the passivated CsPbBr 3 NPLs as blue color convector exhibits no emission saturation even the driving current reaches as high level as 190 mA. This work paves a new way for fabricating high-quality blue emitting NPLs with extraordinary properties.
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
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Xinhua Liu,Peiqing Cai,Yanlin Huang,Xipeng Pu,Qi Ai,Junjie Si,Xin Yao,Gongxun Bai,Zugang Liu
Mn 4+ -activated fluoride phosphors with high luminous efficacy and short decay lifetimes are essential in realizing high-quality warm white-light-emitting diode (WLED) lighting. In this work, Mn 4+ -activated narrow-band red (∼630 nm) phosphor [(CH 3 ) 4 N] 2 HfF 6 was successfully synthesized by introducing an organic cationic group (tetramethylammonium) into the [HfF 6 ] 2- system using a mild chemical co-precipitation method. The sample structure was confirmed using various characterization techniques such as scanning electron microscopy, X-ray diffraction and Raman spectroscopy. Powder particles with diameters ranging from 10 to 20 um and double pyramidal structures were prepared by adjusting the anti-solvent temperature to control the crystal growth rate. The investigation of the morphology, structure and photoluminescence properties of Mn 4+ -doped [(CH 3 ) 4 N] 2 HfF 6 phosphors at different anti-solvent temperatures deepened our understanding of the correlation between structure and luminescence. Ultimately, phosphors with optimal performance (external quantum efficiency, ∼92.2%, and decay lifetime, ∼3.6 ms) were obtained. The samples were mixed with polydimethylsiloxane organosilicon to prepare a red light-conversion flexible film, and the (TMA) 2 HfF 6 :Mn 4+ red phosphor and commercially available YAG:Ce 3+ yellow-green phosphor was thoroughly mixed with transparent silica to form a stable paste, and then coated on a blue LED bead to prepare warm white LEDs, which significantly optimized the performance of the white LEDs (correlated color temperature, ∼5564 K). These experimental results indicate that the materials prepared by the mild solution method have important applications in the domains of display and lighting.
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 ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Xuemei Yao,Yatuan Ma,Xiya Miao,Shulei Li,Yufeng Du,Yun Cheng,Yue Yang,Xianchao Du,Huajuan Deng,Huiling Geng,Ruijin Yu
The propensity of carbon dots (CDs) to undergo significant self-quenching in the solid state, whether due to excessive resonance energy transfer or direct molecule collision, has significantly limited their application in light-emitting diodes (LEDs). However, incorporating electron-deficient boron atoms, guanidine functional groups, and boron hydroxyl groups proves advantageous in forming a hydrogen bond structure network. This network effectively suppresses the self-quenching phenomenon observed in solid CDs, thereby enhancing their potential for use in LEDs. Therefore, on this basis, a series of multicolor tunable solid-state fluorescent CDs were obtained, and their formation mechanism was discussed. The structure and morphology of the prepared series of multicolor tunable CDs were also characterized. The photoluminescence quantum yield (PLQY) of B-CD, Y-CD, and R-CD is 34.3 %, 23.7 %, and 20.5 %, respectively. The prepared series of CDs were used to successfully package the red, blue, and yellow monochromatic LEDs. By adjusting the ratio of CDs of different colors, a single matrix white-LEDs (w-LEDs), two primary colors w-LEDs, and the full-carbon-based w-LED of three primary colors are also obtained. The correlated color temperature of the above three w-LEDs is 7277, 3957, and 5040 K, the Color Rendering Index is 88, 91, and 92, and color coordinates are (0.302, 0.319), (0.376, 0.355), and (0.344, 0.354), respectively. It is demonstrated that CDs are a promising material in the solid-state lighting field.
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
CHEMICAL PHYSICS LETTERS
·
2017
·
IF 1.815
Baochen Wang,Yan-gai Liu,Zhaohui Huang,Minghao Fang
A series of Ca 3 Si 2 O 4 N 2 :Ce 3+ , Tb 3+ phosphors were synthesized and their phase composition and luminescence properties were investigated. Results showed that an efficient energy transfer occurred between the Ce 3+ and Tb 3+ ions. The thermal stability of the Ce 3+ emission was dramatically enhanced upon Tb 3+ doping. The mechanism was attributed to a shift of the configuration coordinate and an increased energy barrier for thermal quenching, which resulted from the enhanced rigid structure of the host. Finally, a white light emitting diode lamp was fabricated, which exhibited excellent properties. These results indicate that Ca 3 Si 2 O 4 N 2 :Ce 3+ , Tb 3+ can serve as promising blue-green emitting phosphors for w-LEDs.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Yanzhi Zhang,Xiaoxu Deng,Ruirui Cui,Xiang Guo,Jun Zhang,Chaoyong Deng
In order to obtain efficient single-phase co-doped phosphors with excellent luminescence properties under near-ultraviolet excitation, Ca 3 Gd 2 Si 3 O 12 : x Dy 3+ (CGSO: x Dy 3+ ) and Ca 3 Gd 2 Si 3 O 12 :0.08Dy 3+ , y Sm 3+ (CGSO:0.08Dy 3+ , y Sm 3+ ) phosphors were effectively manufactured using the classical high-temperature solid-phase method. The phase structure, morphology and XPS test results of the phosphor all show that the Ca 3 Gd 2 Si 3 O 12 (CGSO) material has been successfully synthesized, and Dy 3+ and Sm 3+ ions have been successfully doped into the matrix lattice. Under 362 nm illumination, the PL spectra of CGSO:0.08Dy 3+ , y Sm 3+ phosphor revealed that the typical peak intensity of Dy 3+ ions declined as the amount of Sm 3+ ions increased, whereas the distinctive peak intensity of Sm 3+ ions achieved its maximum at y = 0.07. As Sm 3+ doping grows larger, the fluorescence lifetime shortens, signifying the occurrence of transferring energy among Dy 3+ and Sm 3+ ions, with a maximum efficiency of 81 % being attained. The Ca 3 Gd 2 Si 3 O 12 :0.08Dy 3+ , y Sm 3+ phosphor demonstrates a commendable thermal stability of 90.17 %, with adjustments to the Sm 3+ concentration revealing the potential to yield warm white light, as evidenced by both CIE chromaticity coordinates and CCT measurements. In addition, compared with the phosphor containing only Dy 3+ , the LED assembled with CGSO:0.08Dy 3+ , y Sm 3+ phosphor containing Sm 3+ ions and 365 nm LED chip emits warmer white light with lower color temperature, which confirms the application value of CGSO:0.08Dy 3+ , y Sm 3+ phosphor in the domain of solid-state lighting.
研究领域:
材料科学
·
光学
·
固体照明
✓ 已验证
产品关联
DOI
高影响因子
LUMINESCENCE
·
2018
·Vol. 33
·期 2
·438-442
·
IF 1.671
Ting Li,Zhijun Wang,Panlai Li,Shuchao Xu,Qiongyu Bai,Zhiping Yang
A novel tunable red emitting phosphor LiBaB 9 O 15 :Sm 2+ /Sm 3+ , Li + with broad excitation band was synthesized by a high temperature solid-state method. Luminescence properties were investigated in detail by luminescence, X-ray photoelectron spectroscopy (XPS) spectra and CIE chromaticity coordinates. XPS data confirmed that there were Sm 3+ in LiBaB 9 O 15 :Sm 3+ and Sm 2+ /Sm 3+ in LiBaB 9 O 15 :Sm 2+ /Sm 3+ , respectively. Spectral property of LiBaB 9 O 15 :Sm 3+ , LiBaB 9 O 15 :Sm 3+ /Sm 2+ and LiBaB 9 O 15 :Sm 2+ , Li + presented that the excitation band of Sm 3+ widened and the excitation band of Sm 2+ ranged from 350 to 450 nm. And the red light color is tunable with changing Li + concentration. The results indicated that LiBaB 9 O 15 :Sm 2+ /Sm 3+ , Li + may be promising red phosphor for white light emitting diodes.
研究领域:
材料科学
·
光学
✓ 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）