Results in Chemistry
·
2023
·
IF 2.3
Beibei Zheng,Chufei Miao,Han Xu,Jiaqi Lai,Meng Li,Jumei Tian
Two isostructural lanthanide-based coordination polymers, namely, {[Gd 2 (H 2 dhtp) 3 (DMF) 2 (H 2 O) 4 ]·2DMF·H 2 On ( 1 ) and {[Dy 2 (H 2 dhtp) 3 (DMF) 2 (H 2 O) 4 ]·2DMF·H 2 O}n ( 2 ) (H 4 dhtp = 2,5-dihydroxyterephthalic acid, DMF = N, N-dimethylformamide) were synthesized and structurally characterized by single-crystal X-ray diffraction, IR, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), and elemental analysis. Compounds 1 and 2 exhibited 3D networks and isostructures, except for the distinction of the metal ion. Magnetic measurements indicated that complex 1 exhibited the dominating contribution at low temperature of zero-field splitting for Gd(III) materials, and the complex 2 shown the depopulation of the excited excited state for Dy(III) material. The solid luminescent properties of H 4 dhtp, 1 , and 2 displayed a blue emission band, while the solution state luminescent properties all demonstrated a green emission band. The combination of luminescence sensing and magnetism in single-phase coordination polymers may offer great potential applications in smart multitasking devices.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Yee-Shin Chang,Cheng-Xin You,Tai-Chen Kuo
In this study, SrY₂O₄:Dy³⁺ phosphors were synthesized using the solid-state reaction method and evaluated after heat treatment at 1300 °C for 5 h. XRD analysis confirmed the orthorhombic structure of SrY₂O₄ with residual Y₂O₃ present. The addition of Dy³⁺ ions caused lattice expansion, impacting grain size and crystallinity. SEM images showed that the phosphor particles had irregular shapes with minimal size variation, although they tended to agglomerate due to high-temperature heat treatment. Optical analysis revealed significant absorption and emission peaks, with a strong excitation band in the 200–306 nm range and prominent sharp peaks in the 306–480 nm range, particularly at a 0.5 mol% doping concentration. Emission spectra indicated the highest intensity at 0.5 mol% Dy³⁺ concentration, with intensity decreasing due to concentration quenching at higher levels. Thermal stability tests showed peak emission intensity at 70 °C, with stability maintained up to 190 °C before notable thermal quenching. Chromaticity coordinates remained within the warm white region at both temperatures. This study provides detailed insights into the effects of Dy³⁺ doping on the structural, optical, and thermal properties of SrY₂O₄ phosphors. Compared to previous studies on rare-earth-doped SrY₂O₄ phosphors, this work is the first to systematically explore the substitution of Y³⁺ ions with Dy³⁺ ions until full replacement. The study not only confirmed that the highest emission intensity occurs at 0.5 mol% Dy³⁺ concentration, but also demonstrated that Dy³⁺-doped SrY₂O₄ phosphors exhibit excellent thermal stability, with emission stability maintained below 150 °C. These findings expand the potential applications of Dy³⁺-doped SrY₂O₄ phosphors, particularly in high-temperature environments and solid-state lighting.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Sheng-Jiang Huang,Le-Zhong Li,Xiao-Hui Wu,Jian Tang,Rui Wang,Zhe Xiong,Xin Chang
Considering how quickly wireless communication has developed, the need for the miniaturization, integration and high frequency of electronic components is more intense. The improvement of material properties is the key to solving the difficulties in the development of electronic devices. Solid-phase reactions were used to create Ni 0.5 Zn 0.4 Co 0.1 Dy x Fe 2- x O 4 (NZCDF, 0 ≤ x ≤ 0.1) ferrite ceramics. The produced NZCDF ceramic samples are discovered to still have a spinel structure. The lattice constant a and bulk density d Bulk increase when dysprosium ion is added. The saturation magnetization decreased from 82 to 71 emu/g, and the Hc increased from 18 to 23 Oe. Dysprosium can be added to ceramic samples to modify their level of polarization, lower their ε ′, and minimize their dielectric loss. The DC resistance ρ increases to 6.3 × 10 3 Ω⋅m. In the higher frequency range, with the increase of dysprosium ion content, the magnetic quality factor Q increases significantly, its peak value expands, and its corresponding frequency shifts to a higher frequency. In the high-frequency region, the magnetic quality factor Q rises dramatically, its peak value expands, and its corresponding frequency shifts to a higher frequency. The peak Q of the Ni 0.5 Zn 0.4 Co 0.1 Dy 0.1 Fe 1.9 O 4 sample increased to 14.71, and the frequency corresponding to the peak Q increased to 35.08 MHz. In short, substituting dysprosium ions for nickel-zinc-cobalt ferrite broadens the application range of ferrite ceramics in high-frequency devices. The spectrum of applications for ferrite ceramics in high-frequency devices is expanded by substituting rare earth dysprosium ions for NiZnCo ferrite ceramics.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2024
·
IF 3.8
Qingxue Zhao,Xiaoxia Duan,Tian Tian,Lixin Yi
BaS:Eu,Dy phosphors were prepared by high temperature solid-state method with BaSO 4 as matrix raw material, Eu 2 O 3 and Dy 2 O 3 or Eu 2 (SO 4 ) 3 ·8H 2 O and Dy 2 (SO 4 ) 3 ·8H 2 O as doped ion raw materials. BaSO 4 can be completely reduced after 3 h sintering at 1200 °C in CO atmosphere and pure BaS was obtained in one step. Meanwhile, the rare earth ions were embedded in the host lattices and had no impact on the main structure of the products. However, X-ray diffraction peaks shift shows rare earth doping can cause lattice distortion with the increase of sintering temperature . The luminescence characteristics of BaS:Eu,Dy, BaS:Eu, BaS:Dy and BaS are compared in order to study the luminescence mechanism. It is confirmed that the broad emission locating in the near-infrared (NIR) region should be assigned to 4f 6 5 d 1 →4f 7 transition of Eu 2+ , and the emission locating in the visible region comes from S-related defects in the matrix. Sulfur-rich is particularly detrimental to NIR luminescence. In relatively S-rich systems, there is serious energy transfer between Eu 2+ and S-related defects, which leads to fluorescence quenching. The products are in S-rich state when Eu 2 (SO 4 ) 3 ·8H 2 O and Dy 2 (SO 4 ) 3 ·8H 2 O are selected as raw materials of doped ions. BaS:Eu,Dy inclines to emit visible light with the sintering temperature increasing. By contrast, the products are in Sulfur-deficiency state when Eu 2 O 3 and Dy 2 O 3 are used as raw materials of doped ions and BaS:Eu,Dy only gives NIR emission.
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 MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2024
·Vol. 35
·期 10
·1-12
·
IF 2.8
Ni Hanwen,Zhang Faqiang,He Zichen,Liu Zhifu
The CaTiSiO 5 -based ceramics show promise as dielectric materials for high-temperature MLCC due to their excellent temperature stability which is expected to be improved by co-doping at the A/B sites. In this study, the Dy and Al co-doped CaTiSiO 5 ceramics (Ca 1− x Dy x Ti 1− x Al x SiO 5 , x = 0, 0.005, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08) were fabricated by the conventional solid-state method. The effects of Dy and Al co-doping on the phase structures, dielectric properties and impedance characteristics, were investigated in detail. CaTiSiO 5 -based ceramics transformed to the paraelectric phase and achieved excellent temperature stability of permittivity by Dy and Al doping, which results from the long-range disorder in the arrangement of Ti displacements within the octahedral chain. Components with x = 0.01 showed linear dielectric response under the electric field. It obtained a high and stable dielectric constant in a wide temperature range ( ε r = 52, TCC ≤ ± 180 ppm/°C over the temperature range from − 55 to 300 °C), low loss (tan δ < 0.07), high breakdown strength (∼ 516 kV/cm) and high DC resistance ( ρ = 3.8 × 10 10 Ω cm at 300 °C).
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
MODERN PHYSICS LETTERS B
·
2017
·
IF 0.617
Peiju Hu,Wei Zhang,Zhengfa Hu,Zuyong Feng,Lun Ma,Xiuping Zhang,Xia Sheng,Li Luo,Yinhai Wang
Dy-Bi co-doped yttrium tungstate crystal materials were synthesized by high temperature solid-state method. To reveal the photoluminescence features and properties of the samples, some measurements have been taken. It turned out that different Bi 3 + concentrations play obvious influence in emission performance, and show visible light emission under ultraviolet light excitation. Besides, the effect of temperature on phase structure of samples has also been studied here. Superhigh X-ray luminescence of the phosphors exhibited the promising application in the field of high energy detection. The X-ray irradiation crystal resistance stability of the phosphors has also been investigated through the subsequent testing of XRD and spectra.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS LETTERS
·
2024
·
IF 2.7
Xinlin Yang,Yun Shen,Bijun Fang,Shuai Zhang,Xiaolong Lu,Jianning Ding
Ba(Cu 0.5 W 0.5 )O 3 (BCuW)-doped [(Ba 0.85 Ca 0.15 ) 1-x Dy x ](Zr 0.1 Ti 0.9 )O 3 (BCZT-xDy, x = 0.001, 0.03) ceramics were prepared by conventional ceramic processing via low-temperature sintering technique. Rather pure perovskite structure and densified morphology with irregular nearly spherical-shape grains are achieved in all ceramics due to liquid-phase sintering. All BCuW-doped BCZT-xDy ceramics present apparent dielectric frequency dispersion and relaxor ferroelectric characteristic due to ion substitution and adding BCuW. The ceramics prepared at optimized sintering temperatures have rather large strain and small strain hysteresis, showing prospect application in piezoelectric high-precision actuators.
研究领域:
材料科学
·
陶瓷工程
·
电子材料
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 108
·89238-89243
·
IF 3.84
Bingfu Lei,Wei Li,Haoran Zhang,Jin Wang,Yingliang Liu,Jianle Zhuang,Shi Chen
A simple and effective strategy has been carried out to design a ratiometric temperature sensor in this work. Carbon dots (CDs), which benefit from surface methoxysilyl groups after using an organosilane as a coordinating solvent, are highly reactive intermediates responsible for bonding with silanols and hydroxyl groups from the silica-coated SrAl2O4:Eu,Dy phosphor (SAO). Hence, a CD-grafted SrAl2O4:Eu,Dy phosphor (CD–SAO) could be realized using a facile one-step sol–gel method. The as-prepared CD–SAO shows the characteristic fluorescence emissions of CDs (blue) and SAO (green) at a single excitation wavelength. The temperature dependence of the fluorescence intensity ratios for the two emission bands was studied, and it turned out that the composite has a wide linear temperature sensing range, which matches well with physiologically relevant temperatures. This rather simple approach for creating dual emission enables a completely new strategy for the application of these composites in temperature sensing.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
POLYHEDRON
·
2018
·
IF 2.067
Li-Li Zhu,Peng Hu,Jiang-Fei Cao,Yan-Hua Zhao,Yan-Ni Wu,Yi-Xuan Zhu,Yan Su,Chao Wang
Three new lanthanide-nitronyl nitroxide radical complexes [Ln(tfac) 3 (NIT-2thz)] (Ln(III) = Gd 1, Tb 2, Dy 3; tfac = trifluoroacetylacetonate; NIT-2thz = 2-(2′-thiazolyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) have been synthesized. Single crystal X-ray diffraction analyses reveal that complexes 1 – 3 are isomorphous. They all crystallized in the C2/ c space groups. Each central Ln(III) ion is eight-coordinated by three bischelate tfac ligands and one radical ligand. More specifically, NIT-2thz acts as a chelate ligand to link one Ln(III) ion through its nitrogen atom of the thiazole ring and oxygen atom of the N–O group to form a two-spin system. Magnetic studies show that Gd complex exhibits ferromagnetic Gd(III)–radical coupling, Tb and Dy complexes exhibit frequency-dependent out-of-phase signals.
研究领域:
无机化学
·
材料科学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2019
·Vol. 9
·期 10
·2651-2663
·
IF 5.726
Hairus Abdullah,Dong-Hau Kuo,Noto Susanto Gultom
Hydrogen-evolved Dy-doped Zn(O,S) photocatalysts with different amounts of Dy precursor have been synthesized, characterized and further utilized for hydrogenation reactions. The Dy catalysts are first examined using electrochemical impedance spectroscopy, photo responsivity, and the hydrogen evolution reaction. Dy-doped Zn(O,S) with 10% Dy precursor shows the best photocatalyst performance with the highest H2 production rate of 8.160 mmol g−1 h−1. This catalyst is chosen for conducting the hydrogenation reaction. It is our intention to confirm the correlation between the photocatalytic H2 production rate and the hydrogenation reactions of 4-nitrophenol to 4-aminophenol and azobenzene to aniline, which is a step further in the hydrogenation reaction to challenge the NN bond cleavage of azobenzene. A 100% photo conversion of 60 ppm azobenzene to aniline in 6 h was confirmed under a low-power UV light illumination in a 10% ethanol solution. Kinetic steps and kinetic mechanisms are proposed, which involve the important reaction steps of solvation, adsorption, pinning, and surface hydrogenation reaction operating together.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Linjia Hu,Ruite Liu,Wenkai Zhao,Zaiyang Wang,Feng Guan,Yuchen Wang,Longfei Zhang,Yiguang Jiang,Long Zhang
Perfluoride glass ceramics (FGCs) with SrF 2 /CaF 2 mixed crystals were prepared using a concurrent rapid-quenching-crystallization process. The FGCs contained dense, homogeneous, round crystals of sizes less than 1 μm with high transmittance (exceeding 80 % at 3–8 μm) and low phonon energy (508 cm −1 ). The fluorescence properties of the FGCs doped with Er and Dy were investigated. The energy transfer efficiency between Er and Dy reached 93.81 % and 98.13 %, corresponding to Er: 4 I 11/2 to Dy: 6 H 5/2 and Er: 4 I 13/2 to Dy: 6 H 11/2 , respectively. This enhancement is attributed to the enrichment of rare-earth ions in the crystals induced by phase-separation and low phonon energy of the host material, FGC. Moreover, the average lifetime of Er: 4 I 11/2 in FGC reached 10.13 ms, which is the highest reported value for glass ceramics to our knowledge. This study enriches the research theory of FGC and provides guidance for expanding the properties of materials for mid-infrared photonics.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Xiaoyu Yang,Boming Tang,Xuejuan Cao
Continuous photocatalysis is achieved by using light-storing assisted photocatalytic composites, but little is known about the interactions between photocatalysts and long afterglow materials. g-C 3 N 4 /Sr 2 MgSi 2 O 7 :(Eu,Dy) with a sustained reaction activity was prepared by pyrolysis polymerization, and its optical-photocatalysis behaviors were studied. It was found that the light absorption ability and NO removal effect were improved, but the luminescence-afterglow performance became worse. The interface model of g-C 3 N 4 /Sr 2 MgSi 2 O 7 :(Eu,Dy) was constructed for the first time. On the basis of experimental analyses, its electronic structure and carrier transfer paths were studied by First-principles calculations, and reasons behind the changes in macro performance were revealed. The results showed that Eu 4 f electrons are difficult to return to the Eu 5d orbits after being captured by C 2p orbits, leading to the reduction of light energy radiation; the built-in electric field and energy band offsets between g-C 3 N 4 and Sr 2 MgSi 2 O 7 :(Eu,Dy) promote the transfer of photoinduced carriers, which follows a traditional type-II mechanism, resulting in enhanced photocatalytic activity and decreased luminescence-afterglow performance. This paper reveals the relationship between optical-photocatalysis behaviors and the electronic structure of g-C 3 N 4 /Sr 2 MgSi 2 O 7 :(Eu,Dy). It provides a reference for designing and optimizing light-storing assisted photocatalytic composites.
研究领域:
材料科学
·
环境科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）