LUMINESCENCE
·
2022
·Vol. 37
·期 12
·2018-2027
·
IF 2.613
Guangjin Ou,Hongqing Song,Xinyong Gong,Ruirui Cui,Chaoyong Deng
A new green luminescent phosphor, Li(Y 1- x Tb x )GeO 4 , was prepared using a high-temperature solid-phase method. The X-ray diffraction (XRD) measured spectrum agreed well with the standard card JCPDS No. 02-3479, indicating that it is a quaternary compound belonging to the space group of Pnma(62) with an orthogonal crystalline phase; the excitation and emission spectra measured using the phosphor spectrometer showed that it can be effectively excited by near-ultraviolet light at 378 nm and blue light at 482 nm, and produced excellent strong emission of green light at 550 nm. The afterglow test results show that the sample had a good long afterglow effect at lower doping concentrations; the thermal stability test results showed that its thermal burst activation energy ΔE ≈ 0.37 eV had its excellent thermal stability. The rare earth Tb 3+ -doped green phosphor, LiYGeO 4 :Tb 3+ , has potential applications in household lighting, medical therapy, and optical storage.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FERROELECTRICS
·
2022
·
IF 0.695
Rong Tang,Jinyu Huang,Jing Liao,Jinjin Fu,Bin Deng,Gong-Guo Zhang,Ruijin Yu
A series of novel Sr3WO6:xDy3+ (0.01 ≤ x ≤ 0.35) yellow emitting phosphors are synthesized using the conventional high-temperature solid-state method. The phase analysis and optical properties are discussed in detail. Through the X-ray diffraction (XRD) analysis, the obtained phosphors are identified to be pure phases. The Sr3WO6:Dy3+ phosphors emit bright yellow emission light at 578 nm under 352 nm excitation, which is ascribed to the 4F9/2-6H13/2 transitions. The optimum doping concentration is 0.02 mol. The activation energy Ea is calculated to be 0.154 eV. The Commission International de L'Eclairage (CIE) coordinates and correlated color temperature (CCT) of the Sr3WO6:xDy3+ (0.01 ≤ x ≤ 0.35) is located in the yellow region. All results indicate that the Sr3WO6:Dy3+ phosphors have the potential to be applied in the white light-emitting diode (w-LED) 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
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2019
·Vol. 102
·期 11
·6863-6871
·
IF 3.094
Xiaojun Tan,Shoulei Xu,Xiangyu Wang,Fenhong Liu,Bernard A. Goodman,Dingkang Xiong,Wen Deng
Single crystals of yttria-stabilized zirconia (YSZ) doped with various concentrations of Sm 2 O 3 were synthesized by the optical floating zone method, and their structure and spectroscopic properties characterized using powder X-ray diffraction (XRD), optical absorption, and luminescence measurements. XRD showed that the cubic phase of ZrO 2 was stabilized by addition of Y 2 O 3 and a series of absorption peaks characteristic of Sm 3+ was detected by UV-visible absorption spectroscopy. Three phenomenological J-O oscillator strength parameters Ω t ( t = 2, 4, 6) were calculated to evaluate the local structure and bonding in the vicinity of the Sm 3+ for the 0.75 mol% Sm 2 O 3 : YSZ sample. These were in order of Ω 2 < Ω 4 < Ω 6 with values of Ω 2 = 5.46 × 10 −20 cm 2 , Ω 4 = 10.70 × 10 −20 cm 2 , and Ω 6 = 12.67 × 10 −20 cm 2 , and indicate a relatively high symmetry and low covalent character for the Sm-O bond at the Sm 3+ sites in the YSZ matrix. Photoluminescence spectra recorded under an excitation of 404 nm showed four emission bands centered at 571 nm, 621 nm, 652 nm, and 716 nm corresponding to the transitions 4 G 5/2 → 6 H j ( j = 5/2, 7/2, 9/2, 11/2). The transition probability, lifetime, and branching ratio obtained from the emission spectrum of the 0.75 mol% Sm 2 O 3 : YSZ crystal showed that YSZ is a potential host for Sm 3+ to achieve a reddish-orange laser output, and the Sm 3+ -modified YSZ crystals have a possible use in reddish-orange laser and lighting devices.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2016
·
IF 2.693
Renping Cao,Dedong Peng,Haidong Xu,Shenhua Jiang,Zhiyang Luo,Hui Ao,Pan Liu
Novel NaAl 11 O 17 :Mn 2+ green phosphor is synthesized by solid-state reaction method in air. The emission band peaking at ~508 nm is observed owing to the 4 T 1 → 6 A 1 ( 6 S) transition of Mn 2+ ion, and the chromaticity coordinates are (0.0725, 0.6468). The excitation band peaking at ~360, 382, 424, 450, and 490 nm are attributed to 6 A 1 ( 6 S)→ 4 E( 4 D), 4 T 2 ( 4 D), [ 4 A 1 ( 4 G), 4 E( 4 G)], 4 T 2 ( 4 G), and 4 T 1 ( 4 G) transitions of Mn 2+ ion, respectively, which indicate that NaAl 11 O 17 :Mn 2+ phosphor may be excited by (near) ultraviolet and blue LED chip. The luminous mechanism is explained by Tanabe–Sugano diagram of Mn 2+ ion. The optimal Mn 2+ doping concentration is ~3.5 mol%. The NaAl 11 O 17 :3.5%Mn 2+ phosphor shows high quantum efficiency of ~67.84% with excitation 424 nm. The lifetime decreases from 6.72 to 6.0 ms with increasing Mn 2+ concentration in the range of 0–4 mol%.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2021
·
IF 3.599
Jianxu Wang,Jiang Guo,Qiuyi Lv,Zhijiang Ma,Xuyao Feng,Yuhiu Lu,Jing Gao,Wensheng Chen,Bin Deng,Ruijin Yu
A series of novel orange-red emitting tungstate phosphors, Ca 3 La 2 W 2 O 12 (CLWO): x Sm 3+ (0.005 ≤ x ≤ 0.30) were successfully prepared through the solid-state method at high temperature. The space group is hexagonal R 3 ‾ m . Under 600 nm monitoring, a large charge transfer band from 250 to 340 nm composed of the electron transition of O 2- –Sm 3+ and O 2- –W 6+ and represented the strongest excitation at 300 nm. CLWO:Sm 3+ emitted orange-red light at 600 nm ( 4 G 5/2 – 6 H 7/2 ) under the strongest excitation of 300 nm. The intensity ratio of the electric-dipole and magnetic-dipole of all the samples were bigger than 1. With the Sm 3+ -doped concentration increasing, the upward tendency of ratio values originated from the increased degree of lattice distortion . The calculated R c (21.32 Å) and Q (3.78) represented the dipole–dipole interaction to account for the concentration quenching. With the temperature changing from 300 to 400 K, the chromaticity coordinates of samples just have a tiny difference (Δ x = 1.02 × 10 −4 , Δ y = 1.01 × 10 −4 ). The thermal activation energy was calculated to be 0.42 eV and T 0.5 > 480 K. The color purity of all the phosphors reached 98.9%. Ultimately, a white light-emitting diode (w-LED) was fabricated by coating trichromatic (red, blue, and green) phosphors on a near-ultraviolet chip. The fabricated w-LED revealed a high color rendering index (R a = 91, R 9 = 41) and a good chromaticity coordinate (0.320, 0.363) in the white area. Thus, these orange-red phosphors CLWO:Sm 3+ with high thermal stability and high color purity can be potentially used in w-LED applications.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2019
·
IF 2.961
Renping Cao,Xuantian Wang,Yuming Jiao,Xun Ouyang,Siling Guo,Pan Liu,Hui Ao,Chunyan Cao
NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphors are successfully prepared in air via solid-state reaction method. The crystal structures, concentration-dependent emission spectra , decay curves, and luminescence properties are investigated. The prepared samples have only a single phase (NaCa 2 Mg 2 V 3 O 12 ). The excitation spectrum of host (NaCa 2 Mg 2 V 3 O 12 ) monitored at 510 nm is observed in the region from 210 nm to 400 nm. The host (NaCa 2 Mg 2 V 3 O 12 ) with excitation at 340 nm shows a strong broadband green emission with a maximum at 510 nm in the range of 400–800 nm. The excitation spectrum of NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphor monitored at 618 nm is shown in the region from 210 nm to 550 nm, which includes many absorption peaks. NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphor with excitation at 340 nm displays the tunable emission color in the region from green to yellow light with changing Sm 3+ concentration, however, that with excitation at 406 nm only emits red light. The optimual Sm 3+ concentration is about 4 mol% in NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphor. The lifetime of NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphor decreases from 929.16 μs to 832.11 μs with increasing Sm 3+ concentration. The luminous mechanism of NaCa 2 Mg 2 V 3 O 12 :Sm 3+ phosphor is explained by the configurational coordinate diagram of VO 4 3− and energy level diagram of Sm 3+ ion. The experimental results are beneficial to the research of other Sm 3+ -doped luminescence materials.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2022
·Vol. 16
·期 1
·201
·
IF 3.748
Luping Tang,Chen Liao,Yingqing Guo,Yangyang Zhang
Metal nanoparticles have attracted a great deal of interest due to their unique properties of surface plasmon resonance. Metal nanoparticles can enhance the fluorescence emission intensity of quantum dots (QDs) through the local surface plasmon resonance effect, which is mainly determined by the distance between them. Therefore, it is very important to achieve controllable distance between metal and QDs, and study fluorescence enhancement. In this work, the controllable adjustment of the distance between metal nanoparticles and QDs was successfully realized by controlling the thickness of the SiO2shell of Ag@SiO2nanoparticles. Firstly, Ag nanoparticles with uniform size distribution and relatively high concentration were prepared, and then the thickness of the SiO2shell was controlled by controlling the amount of tetra-ethyl orthosilicate (TEOS) in the hydrolysis of TEOS reaction. (3-aminopropyl) triethoxysilane (APS) was used to connect CdS/ZnS QDs with Ag@SiO2nanoparticles to form Ag@SiO2@CdS/ZnS QD composite nanoparticles. The fluorescence spectra shows that the fluorescence intensity of the Ag@SiO2@CdS/ZnS QD composite nanoparticles is significantly enhanced. Photoexcitation spectra and fluorescence spectra of CdS/ZnS QD and Ag@SiO2@CdS/ZnS QD composite nanoparticles, measured under different energy excitation conditions, indicate that the existence of Ag nanoparticles can enhance the fluorescence intensity of CdS/ZnS QDs. Finally, a further physical mechanism of fluorescence enhancement is revealed.Keywords:Ag-SiO2;fluorescence enhancement;transmission electron microscope;quantum dots;photoexcitation spectra
研究领域:
材料科学
·
光学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 47
·20592-20599
·
IF 3.288
Yuhang Sheng,Aiqing Zhao,Songyan Yuan,Cihui Liu,Xiaowei Zhang,Yunsong Di,Zhixing Gan
Anion exchange reactions in lead halide perovskites provide post-treatment methods to functionalize and modulate their photoelectric properties. However, the mechanism of anion exchange reactions is still fiercely debated. Herein, by investigating time-dependent in situ PL spectra after mixing CsPbBr3 and CsPb(Br0.09/I0.91)3 perovskite nanocrystals (PNCs), the anion exchange process is divided into three stages, i.e. photon reabsorption process, initial anion exchange, and adequate anion exchange. This model is broadly applicable to different situations, ignoring the mixing order or molar ratios between Br and I. This work provides a dynamic model to describe the anion exchange of CsPbX3 PNCs, which will not only add fundamental knowledge to the stability of PNCs, but also guide the post-treatment of PNCs.
研究领域:
材料科学
·
纳米技术
·
光电子学
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2018
·
IF 2.873
Renping Cao,Xinyu Cheng,Lei Su,Ting Chen,Siling Guo,Guotai Zheng,Hui Ao,Wensheng Li
Mg 2 La 2 SnO 7 :Mn 4+ phosphor is synthesized by the solid-state reaction method in air. Monitored at 706 nm, excitation spectrum of Mg 2 La 2 SnO 7 :Mn 4+ phosphor including peaks at ∼ 300, 333, 395, and 516 nm can be observed in the range of 220–600 nm. With excitation at 333 nm, emission band of Mg 2 La 2 SnO 7 :Mn 4+ phosphor is shown in the range of 640–780 nm owing to the 2 E → 4 A 2 transitions of Mn 4+ ion. The optimal Mn 4+ ion concentration is ∼ 0.3 mol% in Mg 2 La 2 SnO 7 :Mn 4+ phosphor. The lifetime decreases from 1.23 to 0.83 ms with the increase of Mn 4+ concentration from 0.1 to 1.2 mol%. There is only one luminescence center (Mn 4+ ) in Mg 2 La 2 SnO 7 :Mn 4+ phosphor, which is confirmed by the luminescence properties, decay curves, and time-resolved emission spectra. Mg 2 La 2 SnO 7 :Mn 4+ phosphor has good thermal stability. Luminous mechanism is explained by energy level diagram of Mn 4+ ion and the thermal quenching phenomenon is analyzed by the configuration coordinate diagram of Mn 4+ ion.
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
ZEITSCHRIFT FUR NATURFORSCHUNG SECTION A-A JOURNAL OF PHYSICAL SCIENCES
·
2022
·Vol. 78
·期 1
·83-88
·
IF 1.712
Arif Ullah,Jinghao Zhuang,Xiaozhan Yang,Wenlin Feng
Red emitting Li 2 CaSnO 4 : x Eu 3+ phosphors were successfully synthesized by the high-temperature solid-state method. The crystal structure, composite and luminescence properties (e.g. the excitation and emission spectra, fluorescent lifetimes, and CIE chromaticity coordinates) of the samples were investigated by X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM), energy dispersive spectrometer (EDS) and spectral analysis technique. The emission spectra consist of the characteristic peak resultant to Eu 3+ under the excitation of 395 nm and the dominant emission peak is at 621 nm ( 7 F 0 → 5 L 6 ). The optimal red emission was obtained through 4% Eu 3+ doping. These new red Li 2 CaSnO 4 : Eu 3+ phosphors have the potential application for white LEDs.
研究领域:
材料科学
·
光电技术
·
固体化学
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2014
·
IF 2.075
Renping Cao,Fenxiang Zhang,Chunyan Cao,Xiaoguang Yu,Aihui Liang,Siling Guo,Hongdong Xue
CaAl 2 − y O 4 : y Mn 4+ ( y = 0–1.6 mol%) phosphors are synthesized by a solid-state reaction method in air, and their crystal structure and luminescence property are investigated. To compare luminescence property, CaAl 3.99 O 7 :1%Mn 4+ and SrAl 1.99 O 4 :1%Mn 4+ phosphors are also synthesized at the same condition. Broad band excitation spectra are observed within the range 220–550 nm, and emission spectra cover from 600 to 720 nm with the strongest emission peak at ∼658 nm owing to the 2 E → 4 A 2 transition of Mn 4+ ion. The influence of crystal field to luminous intensity is discussed, and the possible luminous mechanism of Mn 4+ ion is explained by using energy level diagram of Mn 4+ ion. CaAl 1.99 O 4 :1%Mn 4+ , CaAl 3.99 O 7 :1%Mn 4+ , and SrAl 1.99 O 4 :1%Mn 4+ phosphors under excitation 325 nm light emit red light, and their CIE chromaticity coordinates are (0.7181, 0.2813), (0.7182, 0.2818), and (0.7198, 0.2801), respectively. These contents in the paper are helpful to develop novel and high-efficient Mn 4+ -doped phosphor for white LEDs.
研究领域:
材料科学
·
光学
·
化学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Tongxu Gu,Zhengyan Li,Zhaohui Ren,Xiang Li,Gaorong Han
Simultaneous detection of multiple types of microRNA (miRNA) is of great significance in early cancer diagnosis. In this study, rare-earth-doped CaF 2 upconversion nanocrystals (CaF 2 : RE 3+ , namely Ho 3+ or Tm 3+ and Yb 3+ ) are formed within the mesopores of silica nanoparticles (CaF 2 : RE 3+ @MSN), in an in-situ manner, by capillary effect and thermo-decomposition method. Comparing to current upconversion nanoparticles, the amorphous and mesoporous nature of CaF 2 : RE 3+ @MSN provides abundant active groups and high specific surface area for feasibly immobilizing oligonucleotide probe. The simultaneous and selective detection of multiple miRNAs was achieved based on the photoluminescence spectra of different CaF 2 : RE 3+ @MSN conjugated with DNA probes in the same solution. The results indicated that the proposed approach holds significant potential for multiple miRNA detection and offers an opportunity for cancer early diagnosis.
研究领域:
纳米技术
·
生物医学工程
·
分析化学
·
分子生物学
✓ 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）