MATERIALS RESEARCH BULLETIN
·
2017
·
IF 2.446
Chunlong Han,Li Luo,Guoshuai Dong,Wei Zhang,Yinhai Wang
Novel YAG:Ce 3+ , Pr 3+ , Yb 3+ phosphors were synthesized using a high temperature solid state reaction method. The XRD patterns revealed that the obtained samples belong to the single phase YAG. The optical spectra demonstrated that Pr 3+ could be a bridge to facilitate the energy transfer from Ce 3+ to Yb 3+ in the YAG host. Blue light excited Ce 3+ and a yellow emission from Ce 3+ together with a near infrared emission of Yb 3+ was obtained. The effect of Pr 3+ doping on the energy transfer efficiency was explored. When the doping concentration of Pr 3+ increased, the yellow emission intensities of Ce 3+ decreased and the near infrared emission intensity of Yb 3+ increased monotonously. Hence, the efficiency of energy transfer from Ce 3+ to Yb 3+ is enhanced by the addition of Pr 3+ , implying that the YAG:Ce 3+ , Pr 3+ , Yb 3+ phosphors are promising downshifting materials and have the potential to be used in Si-based solar cells.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2019
·Vol. 24
·期 23
·4275
·
IF 3.06
Qian-Chun Zhang,Wu-Li Yan,Li Jiang,Yu-Guo Zheng,Jing-Xin Wang,Run-Kun Zhang
In this work, we successfully developed a novel and sensitive gas sensor for the determination of trace acetophenone based on its cataluminescence (CTL) emission on the surface of nano-praseodymium oxide (nano-Pr6O11). The effects of working conditions such as temperature, flow rate, and detecting wavelength on the CTL sensing were investigated in detail. Under the optimized conditions, the sensor exhibited linear response to the acetophenone in the range of 15–280 mg/m3(2.8–52 ppm), with a correlation coefficient (R2) of 0.9968 and a limit of detection (S/N = 3) of 4 mg/m3(0.7 ppm). The selectivity of the sensor was also investigated, no or weak response to other compounds, such as alcohols (methanol, ethanol,n-propanol,iso-propanol,n-butanol), aldehyde (formaldehyde and acetaldehyde), benzenes (toluene,o-xylene,m-xylene,p-xylene),n-pentane, ethyl acetate, ammonia, carbon monoxide, carbon dioxide. Finally, the present sensor was applied to the determination of acetophenone in human exhaled breath samples. The results showed that the sensor has promising application in clinical breath analysis.Keywords:cataluminescence;sensor;acetophenone;Pr6O11
研究领域:
分析化学
·
医学检测
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2019
·
IF 5.107
Yusheng Yang,Chaoqun Lan,Lingyun Guo,Zhuoqing An,Zengwu Zhao,Baowei Li
Tens of thousands of tons of rare-earth permanent magnet (REPM) wastes are produced worldwide every year. The recovery of rare-earth elements from the wastes can effectively reduce the exploitation of rare-earth minerals. The recovery of neodymium and praseodymium from a REPM waste is investigated by electrolysis in molten LiF-CaF 2 where no anode gas releases, making the process environmentally attractive. Neodymium and praseodymium are selectively oxidized from the REPM waste and transformed into rare-earth ions. To facilitate the oxidation of rare-earth elements inside the REPM waste, we intended to make REPM electrode form channels by oxidation of Nd-Pr and Nd 2 Fe 14 B alloys. By analyzing the microstructure of REPM electrode after forming channels, it can be found that the channels provide continuous transport access of the electrolyte to the inside of the REPM electrode. The separation rates of Nd and Pr increase with increasing current, while the rate of oxidation reaction is proportional to current. In addition, the oxidation of Fe initially occurs at the inside of the REPM electrode where rare-earth elements have been first depleted. The separated rare-earth ions are directly prepared as rare-earth metals at the cathode by electrolysis, leaving the porous Fe 2 B alloy and metallic Fe.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2022
·Vol. 51
·期 3
·1180-1188
·
IF 2.047
Ji Xinran,Zhou Ke,Zhao Ye,Sun Meiling,Dong Shijun,Zhang Hongbo,Cao Hechun,Zheng Hui,Wu Qiong,Zhang Yang
The regulation of magnetic and dielectric properties for yttrium iron garnet ferrites by ion doping is highly desirable in microwave devices. In this work, yttrium iron garnet ferrites co-doped with Pr-Zn-Zr atoms with the chemical formula Pr x Y 3-x Zn 0.1 Zr 0.1 Fe 4.8 O 12 (x = 0, 0.1, 0.15, and 0.2) were prepared. The dependence of the crystal structure, microstructure, magnetic, and dielectric properties of the obtained samples on the Pr doping concentration was investigated. The morphologies and crystal structure characterizations confirm that the Pr ion has effectively doped in the yttrium iron garnet ferrites and increased the lattice parameter and grain size. The magnetic characterization shows that the saturation magnetization also increases with the Pr concentration and obtains a maximum value of 27.68 emu/g at x = 0.15. Additionally, the doping of Pr increases the magnetic anisotropy constant K 1 which increases ferromagnetic resonance linewidth. Lastly, the dielectric properties measurement further indicates that Pr doping improves both real and imaginary parts of permittivity, and the highest value of the real part of the permittivity is obtained at x = 0.15. Consequently, the crystal structure, microstructure, magnetic properties, and dielectric properties of garnet ferrite can be effectively regulated by the Pr doping concentration, and excellent properties of the ceramic can be obtained at x = 0.15, which allows potential applications in microwave devices.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2020
·Vol. 26
·期 25
·5654-5661
·
IF 4.857
Xiao-Yi Song,Yu-Hang Zhang,Ping-Ping Sun,Jun Gao,Fa-Nian Shi
Graphical Expanded capacity : Three Ln−Li metal–organic frameworks (MOFs; Ln=Ce and Pr) were successfully designed and structurally characterized. The unique electrochemical performances of Ln−Li MOFs lead to promising applications as next-generation electrode materials for lithium-ion batteries. Novel lithium–lanthanide (Ln: cerium and praseodymium) bimetallic coordination polymers with formulas C 10 H 2 LnLiO 8 (Ln: Ce (CeLipma) and Pr (PrLipma)) and C 10 H 3 CeO 8 (Cepma) were prepared through a simple hydrothermal method. The three compounds were characterized by means of FTIR spectroscopy, X-ray diffraction, single-crystal X-ray diffraction, SEM, TEM, and X-ray photoelectron spectroscopy. The results of structural refinement show that they belong to triclinic symmetry and P space group with cerium (or praseodymium) and lithium cations, forming coordination bonds to oxygen atoms from different pyromellitic acid molecules, and leading to the construction of 3D structures. It is interesting to note that the frameworks exclude any coordination water and lattice water. As an electrode material for lithium-ion batteries, CeLipma exhibits a maximum capacity of 800.5 mAh g −1 and a retention of 91.4 % after 50 cycles at a current density of 100 mA g −1 . The favorable electrochemical properties of the lanthanide coordination polymers show potential application prospects in the field of electrode materials.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 14
·3417
·
IF 4.2
Pengfei Zhu,Zhaoxia Hu,Shouwen Chen
The development of economical catalysts that exhibit both high activity and durability for chlorinated volatile organic compounds (CVOCs) elimination remains a challenge. The oxidizing and acidic sites play a crucial role in the oxidation process of CVOCs; herein, praseodymium (Pr) was introduced into CrOx catalysts via in situ pyrolysis of MIL-101(Cr). With the decomposition of the ligand, a mixed micro-mesoporous structure was formed within the M-Cr catalyst, thereby reducing the contact resistance between catalyst active sites and the 1,2-dichloroethane molecule. Moreover, the synergistic interaction between chromium and praseodymium facilitates Oβspecies and acidic sites, significantly enhancing the low-temperature catalytic performance and durability of the M-PrCr catalyst for 1,2-dichloroethane (1,2-DCE) oxidation. The M-30PrCr catalyst possess enhanced active oxygen sites and acid sites, thereby exhibiting the highest catalytic activity and stability. This study may provide a novel and promising strategy for practical applications in the elimination of 1,2-DCE.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Chenwei Xiong,Rui Hao,Kewen Tao,Huashan Li,Shaopeng Lin,Decai Ma
This study has demonstrated that lithium niobate doped with praseodymium (LiNbO 3 :Pr), which initially did not exhibit persistent luminescence(PersL), can display significant PersL performance through the modulation of the lithium-to-niobium ratio (R LN ). By adjusting the R LN to 1, LiNbO 3 :Pr achieved enhanced PersL, lasting several minutes, with the afterglow's duration further influenced by the R LN . Thermoluminescence (TL) assays and energy diagram analyses have elucidated that the presence and depth of oxygen vacancy defects are critical for both the emergence and longevity of PersL LiNbO 3 :Pr polycrystals . These insights enhance the understanding of PersL mechanisms in lithium niobate crystals and highlight their potential for application in optical information storage.
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
·
2022
·
IF 5.532
Yehong Zhang,Xiangyu Li,Zhidong Pan,Shanjun Ke,Yanmin Wang
This paper was to synthesize praseodymium-doped neodymium molybdate allochroic pigments with different molar ratios of molybdenum (Mo), neodymium (Nd) and praseodymium (Pr) through solid-state reactions. The pigments synthesized were investigated by X-ray diffraction (XRD), selected area electron diffraction (SAED), thermogravimetry and differential thermal analysis (TG-DSC), diffuse reflectance spectroscopy , X-ray photoelectron spectroscopy (XPS) and colorimeter. The results show that a pure neodymium molybdate (i.e., Nd 2 MoO 6 ) can be formed after sintering at 1000 °C for 3 h, and praseodymium-doped neodymium molybdate can be synthesized after sintering at 1000 °C for 3 h due to praseodymium ions entering in the lattice of Nd 2 MoO 6 . The crystal structure in the pigment synthesized can transform from cubic to tetragonal depending on the molar ratio of neodymium/molybdenum and sintering procedure. The color properties of pigments were measured in color space CIE L*a*b* under different standard illuminants (i.e., solar-light (D65), incandescent light (A), cool white fluorescent lamp (F2), and three-band fluorescent lamp (F11)). The results show that the colors of the pigments vary under different illuminants. According to the color difference (Δ E ) analysis, neodymium molybdate pigment exhibits a maximum color difference of 10.69, and the maximum color difference of praseodymium-doped neodymium molybdate pigment with doping content of 0.2 increases to 17.63 due to the Pr 3+ ions substitution for Nd 3+ ions in the lattice. In addition, the color difference of the pigments with allochroic effect was discussed based on the colorimetry. The color difference of the pigments is due to a high reflectance region at 540–550 nm and a low reflectance region at 380–500 nm.
研究领域:
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
Chinese Physics B
·
2024
·Vol. 33
·期 12
·127501
·
IF 1.5
Changji Xu,Xinyu Jiang,Zhengguang Zou,Zhuojia Xie,Weijian Zhang,Min Feng
The structural, magnetic and magnetocaloric properties of perovskite manganites La0.67Sr0.28Pr0.05Mn1−xCoxO3 (x = 0.05, 0.075 and 0.10) (LSPMCO) are investigated. LSPMCO crystallizes as a rhombohedral structure with R-3c space group. As the Co content increases, the cell volume expands, the Mn–O–Mn bond angle reduces and the length of the Mn–O bond increases. The samples show irregular submicron particles under a Zeiss scanning electron microscopy. The particle size becomes larger with increasing doping. The chemical composition of the samples is confirmed by x-ray photoelectron spectroscopy (XPS). The ferromagnetic (FM) to paramagnetic (PM) phase transition occurs near the Curie temperature (TC), and all transitions are second-order phase transitions (SMOPT) characterized by minimal thermal and magnetic hystereses. Critical behavior analysis indicates that the critical parameters of LSPMCO closely align with those predicted by the mean-field model. The TC declines with Co doping and reaches near room temperature (302 K) at x = 0.075. The maximum magnetic entropy change (-\Delta {S}_{{\rm{M}}}^{\max }) at x = 0.05 is 4.27 J/kg⋅K, and the relative cooling power (RCP) peaks at 310.81 J/K. Therefore, the system holds significant potential for development as a magnetic refrigeration material, meriting further professional and objective evaluation.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·Vol. 48
·期 47
·20061-20070
·
IF 2.7
Jiabing Chen,Yibo Tang,Xiaojun Lu,Zijing Lu,Xingmao Jiang
The industrial production of methyl propionate synthesized via methoxycarbonyl esterification of ethylene achieved 100% atom economy. In this study, we synthesized ruthenium-loaded praseodymium–cerium oxide (Pr–CeO2) catalysts by precipitation impregnation and evaluated their performance in the methoxycarbonylation reaction of ethylene. The effect of Pr doping on the reaction results was analyzed by characterization and mechanistic studies. Pr doping increased the concentration of localized oxygen vacancies in the catalysts and thus modulated the catalytic effect of Lewis acid–base pairs. The increase of local oxygen vacancies significantly enhanced the activation and dissociation of CH3OH. At the same time, since the dissociation activation of the other two feedstock molecules, ethylene and CO, occurred at the Ru site, Pr doping facilitated the dispersion of Ru to a certain extent, thus increasing the dissociation activation of CO and ethylene, which, in combination with Pr doping, further increased the content of oxygen vacancies in the active site as methanol, resulting in a substantial enhancement of the dissociation activation of the feedstock molecules, which then increased the catalytic reaction rate through synergistic effects. The results provide a new perspective for the future study of methoxycarbonylation.
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
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Tao Wang,Junling Yu,Jianmin Liu,Feng Jiang,Guo Feng,Jian Liang,Lifeng Miao,Quan Zhang,Qian Wu,Xinbin Lao
A fluorine-free route has been developed to fabricate V/Pr co-doped zircon (ZrSiO 4 ) ceramic pigments with Na 3 VO 4 and Pr(NO 3 ) 3 ·6H 2 O as colourants . The as-prepared pigments were characterized by XRD , Raman, XPS , UV–vis, FE-SEM, TEM and automatic colourimeters . The results show that Na 3 VO 4 can not only act as colourant to produce blue hue, but as mineralizer to accelerate the formation of V/Pr co-doped ZrSiO 4 pigment. A colour tuning between blue, green and yellow can be achieved by increasing the mole ratio of Pr/V, and the most intense yellow hue (L* = 74.55, a* = −0.38, b* = 46.82) is obtained at a mole ratio of Pr/V = 0.5. Both Pr 4+ and Pr 3+ cations are co-existed in the pigments, where Pr 4+ contributes to the generation of yellow hue while Pr 3+ undermines the yellow hue. The good chromatic ability in glaze at high temperature suggest its potential application in ceramic decoration.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2011
·
IF 3.65
Xue Wang,Chao Yang,Tingmei Wang,Peng Liu
We report the synthesis of a series of praseodymium oxide/polypyrrole (Pr 6 O 11 /PPy) nanocomposites , and their application in the electrochemical energy storage . The Pr 6 O 11 /PPy nanocomposites were synthesized by the in situ surface-initiated polymerization technique based on the amine-functionalized Pr 6 O 11 nanoparticles . The nanocomposites exhibit the well-defined core/shell structure observed by transmission electron microscopy (TEM) and scanning electron microscope (SEM). Thermogravimetric analysis reveals a significantly enhanced thermal stability with the addition of the amine-functionalized Pr 6 O 11 nanoparticles. Furthermore, they possess weak temperature dependence of the conductivity and the highest specific capacitance of 400 F g −1 at the charge–discharge current density of 10 mA cm −2 in 1.0 M NaNO 3 electrolyte solution when being used as the electrode material for supercapacitor .
研究领域:
材料科学
·
电化学
✓ 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）