JOURNAL OF LUMINESCENCE
·
2021
·
IF 3.599
Lei Yu,Kuibao Zhang,Weiwei Li,Baozhu Luo
In this study, Sm-doped Gd 2 Zr 2 O 7 transparent ceramics were successfully prepared by high temperature vacuum sintering using combustion synthesized nanopowders . X-ray diffraction, solid ultraviolet absorption spectrophotometer and fluorescence spectrometer were employed to investigate the structural evolution and photoluminescence properties of as-prepared samples. The Sm-doped Gd 2 Zr 2 O 7 nanopowders are in defective fluorite structure, which transforms into pyrochlore structure after high temperature sintering . The 3% Sm-doped sample exhibits high in-line transmittance of 74.7% at the wavelength of 1000 nm. The fluorescence lifetimes of all samples excited at 404 nm and detected at 615 nm are in millisecond scale, and the concentration quenching occurs when the Sm doping concentration reaches to 10%.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2015
·
IF 4.642
Yuehua Chen,Huiyong Wang,Yuanchao Pei,Jiao Ren,Jianji Wang
The recovery of rare-earth metals from waste materials is very important due to the risks associated with having a low supply of them in the future. In this work, hydrophobic 1-alkylcarboxylic acid-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquids, [(CH2)nCOOHmin][Tf2N] (n = 3, 5, 7), were synthesized and used to separate neodymium (III) from Fe(III) and samarium (III) from Co(II) in aqueous solutions. The factors affecting the solvent extraction process such as phase volume ratio, contact time, pH value of the aqueous phase, alkyl chain length of the ionic liquids, and temperature of the system were examined systematically. It was found that the maxmium extraction efficiency of the investigated metal ions was as high as 99%, and Sm(III) and Nd(III) could be selectively separated from Co(II) and Fe(III), with separation factors of 104–105, by simply modulation of the aqueous phase pH. After extraction, about 97% of the metal ions could be stripped from ionic liquid phase in a single stripping step by using dilute aqueous HCl or oxalic acid, and the ionic liquids would be recovered and reused in the next extraction process. These results indicate that the ionic liquids developed here are useful for the selective recovery of rare-earth metals from NdFeB and SmCo permanent magnets.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2022
·Vol. 38
·期 6
·1547-1552
·
IF 2.726
Jin Huan,Xu Ding,Tian Chao,Yue Yinghong,Hua Weiming,Gao Zi
A series of Sm-doped CeO 2 /Beta composite catalysts with various Sm/Ce atomic ratios(0.1–0.4) were prepared by an incipient impregnation method, followed by calcination at 650 °C. They were characterized by X-ray diffraction(XRD), N 2 adsorption, X-ray photoelectron spectroscopy(XPS), Raman, NH 3 -temperature programmed desorption(TPD) and CO 2 -TPD. The incorporation of Sm into CeO 2 /Beta increases obviously the propylene yield for the selective conversion of ethanol to propylene. The promoting effect of Sm on CeO 2 /Beta can be attributed to two reasons. One is more acetone intermediates are generated on the Sm-doped catalysts due to the enhanced formation of oxygen vacancies. The other is the conversion of acetone intermediate to propylene is enhanced owing to weaker and fewer acid sites on the Sm-doped catalysts.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Hong Zhang,Qian Du,Xin Du,Zhanglian Xu,Shaoqiang Guo,Wentao Zhou
The electrorefining of spent nuclear fuels in a molten LiCl-KCl salt electrolyte recovers the valuable actinides but also releases radioactive fission products in the salt. To minimize the nuclear waste volume, dissolved fission products such as rare earths (REs) must be removed from the electrorefining salt and immobilized into proper wasteforms. Here we propose a two-step approach for treating the electrorefining waste salt by (i) the electrolytic recovery of REs from the salt using a liquid metal cathode; and subsequent (ii) oxidative extraction of REs from the liquid metal into durable wasteforms. Experimental demonstration using rare earth element samarium (Sm) and liquid metal (Bi) was successful. The Sm ions dissolved in the salt can be selectively recovered as dendrite Sm-Bi intermetallic products on the top of liquid bismuth cathode through electrolysis at appropriate applied currents or potentials. Then the Sm in the Sm-Bi alloy was efficiently extracted into both zinc-in-titania (ZIT) glass ceramic and lanthanide aluminoborosilicate (LABS) glass wasteforms through selective oxidation at Sm 2 O 3 loadings of 18–25 wt% and 50 wt%, respectively. Recycling of the electrorefining salt with minimum nuclear waste generation is foreseeable with the use of this simple, efficient, and highly compatible process.
研究领域:
核化学与技术
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
BULLETIN OF MATERIALS SCIENCE
·
2015
·Vol. 38
·期 5
·1149-1154
·
IF 1.017
DENG TIAN,ZHANG CHONGRONG,XIAO YUYUAN,XIE ANRAN,PANG YUE,YANG YANZHAO
The samarium-doped ceria (SDC) nanospheres were prepared by the one-step hydrothermal method and characterized by transmission electron microscope, scanning electron microscope, powder X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive spectrometer and Raman spectra. According to the results, samarium was doped into the lattice successfully. The as-prepared samples were dispersed well and the average diameter was 60 nm. It showed better catalytic performance than pure ceria and the most appropriate concentration of doping was found.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2016
·Vol. 100
·期 2
·686-696
·
IF 2.787
Qingqing Yang,Bin Meng,Zuoliang Lin,Xinkun Zhu,Feng Yang,Shan Wu
To further enhance the electrical conductivity of doped ceria, the samarium-doped ceria (SDC)/Al 2 O 3 nanocomposites were prepared through sintering the coprecipitated powders in 1100°C-1300°C. The grain sizes of all composites are less than 100 nm and decrease with alumina addition. Besides the main phases of SDC and Al 2 O 3 , the SmAlO 3 can precipitate in the composites if sintered at higher temperatures or for longer dwell time. The deviations of SDC diffraction peak positions demonstrate the solid solution of alumina into SDC lattice. The total electrical conductivities of the composites increase with alumina content until 30% alumina is added. The SDC/30%Al 2 O 3 presents the higher total conductivity than the pure SDC by about five times. Specifically, the grain interior conductivity generally decreases with the alumina addition while the grain-boundary conductivity increases with that. The introduction of the conductive SDC/Al 2 O 3 interface can contribute to the rise of total conductivity, yet the excessive alumina addition also blocks the oxygen ion conduction. The SmAlO 3 precipitation is detrimental to the ion conduction for it consumes part of alumina and leads to the decrement in Sm concentration of SDC grain. Appropriate alumina addition not only enhances the conductivity of SDC but also lowers the material cost.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Haochen Sun,Yingzhi Meng,Feifei Han,Silin Tang,Xiuyun Lei,Qingqing Ke,Dingyuan Wang,Yisong Bai,Biaolin Peng,Xue Chen,Xiang Niu,Shengguo Lu,Laijun Liu
Electrocaloric refrigeration technology has garnered significant attention due to its potential for next-generation solid-state cooling, which is miniaturized and efficient. However, achieving a substantial electrocaloric effect (ECE) and a wide working temperature range at low electric fields remains a challenge. In this study, a synergistic approach combining domain and defect engineering was used in transparent 0.88 Pb(Mg 1/3 Nb 2/3 )O 3 -0.12PbTiO 3 - x Sm(0.88PMN-0.12 PT- x Sm) ceramics to improve ECE and temperature stability. Finally, a notable adiabatic temperature change ( ΔT ) of 2.07 K in the x = 0.01 ceramic, with ΔT exceeding 1.0 K across a broad temperature range from 30 to 180 °C was achieved. Piezoresponse force microscopy (PFM) and X-ray photoelectron spectroscopy revealed the presence of small domains and appropriate oxygen vacancies as contributors to the enhanced ECE and broad operation temperature range. This work introduces a promising candidate material for electrocaloric refrigeration.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2024
·Vol. 53
·期 28
·11713-11719
·
IF 3.5
Haoran Yu,Jian Guo,Jiajia Wang,Ji Zhang,Shan-Tao Zhang
As the two typical basic binary solid solutions of the relaxor-PbTiO3 family, Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) has been widely investigated, whereas Pb(Ni1/3Nb2/3)O3-PbTiO3 (PNN-PT) has not. Here, 1.5 mol% Sm-doped (1 − x)Pb(Ni1/3Nb2/3)O3–xPbTiO3, (1 − x)PNN–xPT:0.015Sm with x = 0.33–0.39, ceramics have been prepared and the chemical composition-induced evolution of crystal structure, domain, and electrical properties investigated systematically. With increasing PT content, evolution of the rhombohedral–tetragonal structure was observed. A rhombohedral–tetragonal morphotropic phase boundary occurred around x = 0.36–0.37, which showed a peak piezoelectric property with piezoelectric constant d33 = 531 pC N−1 and planar electromechanical coupling factor kp = 0.37 at room temperature. At the same time, the x = 0.36 composition showed improved ferroelectric behavior with remanent polarization Pr = 13.4 μC cm−2 and coercive field Ec = 3.2 kV cm−1. Interestingly, different from its PMN-PT counterpart, there is no temperature-driven phase transition between room temperature and the Curie temperature for (1 − x)PNN–xPT:0.015Sm. These parameters indicated that the PNN-PT system is worthy of more attention and is a promising platform for further development of high-performance piezo/ferroelectric materials.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Wenzhi Su,Shoujun Ding,Chuancheng Zhang,Miaomiao Wang,Hao Ren,Haitang Hu,Yong Zou,Wenpeng Liu
A series of trivalent samarium ions (Sm 3+ ) doped double perovskite Sr 2 LuNbO 6 ( x at% Sm 3+ :Sr 2 LuNbO 6 , x = 0.5–15) phosphors have been prepared via high-temperature solid-state method. The structural characterization of these phosphors was conducted employing X-ray diffraction (XRD), XRD Rietveld refinement , scanning electron microscope (SEM) and transmission electron microscope (TEM), respectively. Density functional theory calculations utilizing the Vienna ab initio simulation package (VASP) were employed to unveil the electronic structures, encompassing the band structure and density of states (DOS). Photoluminescence (PL) spectroscopy was employed to scrutinize the luminescent properties, while the thermal stability of the PL spectra was also evaluated. The most prominent emission peak, exhibiting an orange-reddish hue, was observed at 601 nm upon excitation at 406 nm. The quenching mechanism of Sm 3+ ions within the Sr 2 LuNbO 6 host lattice was identified as a dipole-dipole interaction, with the quenching concentration of 3 at%. Moreover, the phosphors demonstrated excellent thermal stability, with an activation energy ( E a ) value of 0.126 eV. These findings collectively underscore the promising potential of Sm 3+ :Sr 2 LuNbO 6 orange-reddish phosphors for applications in white light-emitting diodes (w-LEDs).
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2024
·
IF 5.4
Xiuxiu Li,Enyi Hu,Faze Wang,Peter D. Lund,Jun Wang
Samarium oxide (Sm2O3) is a promising electrolyte for low-temperature fuel cells but lacks further exploration of performance optimization. Herein, we propose an effective approach to strengthen the proton transport characteristics via constructing a heterostructure interface in a Sm2O3/ZnO composite electrolyte. The constructed optimal 6Sm2O3-4ZnO cell device yields an improved peak power density of 920 mW cm–2 and an extended durability performance of 45 h at 500 °C. Experiments confirm the proton conduction, and the density functional theory calculation further discloses the low proton migration energy of 0.35 eV. The semiconductor junction test and theoretical calculation both reveal that the heterojunction exists at the Sm2O3/ZnO interface. The strong local electric field strength of 1.53 × 107 V m–1 at the interface effectively suppresses short circuit and accelerates proton transport, leading to significantly enhanced electrochemical performance. This study indicates that the 6Sm2O3-4ZnO material is a promising electrolyte candidate for fuel cell application.
研究领域:
材料科学
·
能源工程
✓ 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
ACS Catalysis
·
2022
·
IF 13.7
Xilun Zhang,Lin Liu,Anan Wu,Junfa Zhu,Rui Si,Jianping Guo,Ruting Chen,Qike Jiang,Xiaohua Ju,Ji Feng,Zhitao Xiong,Teng He,Ping Chen
Metal-oxide-supported Ru catalysts, typically in the form of Ru particles dispersed on oxides, have emerged as the most promising catalysts for the ammonia synthesis reaction. Generally, Ru particles are regarded as catalytically active components and are mainly responsible for the formation of ammonia during ammonia synthesis. Here we show that subnano Ru clusters on Sm2O3 (Ru/Sm2O3) favor the formation of surface hydride (Sm–H) species under reaction conditions, which can trigger the activation of Ru clusters in the ammonia synthesis reaction. The synergy of surface hydride species and Ru clusters boosts the activity relative to Ru clusters alone and affords ammonia yields as high as 90.1–100% of the thermodynamic equilibrium value at 400 °C. Mechanistic studies and theoretical calculations reveal that Sm–H species can not only work in synergy with Ru clusters to reduce the energy barrier for nitrogen dissociation, but also directly participate in the formation of ammonia on the Ru clusters. The discovery of the synergy role of surface hydride species can deepen the molecular-level understanding of the ammonia synthesis reaction process, which will eventually help to rationally design efficient oxide-supported metal catalysts in the heterogeneous catalysis process where hydrogen is involved.
研究领域:
催化化学
·
材料科学
✓ 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）