APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Jiayi Qi,Xingkun Qi,Yan Pan,Junshuo Cui,Ying Xiong,Weijun Shan,Haibiao Yu
Sm 0.06 Ni with excellent H 2 O resistance for eliminating N 2 O was prepared by co-precipitation method. Research indicated that the introduction of Sm into Sm 0.06 Ni has the following effects: (1) Sm species (Sm 2 O 3 ) highly dispersed on the surface of Sm 0.06 Ni catalyst, which not only decreased the crystallite size of NiO, but also produced a certain number of edge dislocations and defects. (2) Sm 2 O 3 weakened the Ni-O band and increased the number of active sites. (3) The redox cycle of Ni 2+ + Sm 3+ ↔ Ni 3+ + Sm 2+ was formed on the surface of Sm 0.06 Ni during the reaction. Based on the above changes, Sm 0.06 Ni exhibited superior catalytic performance and much lower E a for the reaction compared with pure NiO. Over Sm 0.06 Ni, the TOF at 350 ℃ was 4.1 × 10 −3 s −1 , 37 times of that over pure NiO. More importantly, Sm 0.06 Ni exhibited excellent H 2 O resistance performance under submitted real reaction conditions, about 76 % N 2 O conversion can be obtained at 400 ℃.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2023
·
IF 3.8
Shuo Shan,Jie Li,Xuan Zhao,Siwen Pi
M-type barium ferrite with the formula Ba 1− x Sm x Fe 12− y Nb y O 19 ( x = 0.00–0.10, y = 0.00–0.20), which was co-doped with Sm 3+ and Nb 5+ ions, was synthesized experimentally by a modified solid-phase reaction method. The crystal structure of samples was determined by X-ray diffraction, which confirmed that they were of high purity. The X-ray diffraction data were fitted with a full-spectrum correction using GSAS software. By Fourier transform infrared spectroscopy, the samples were observed to exhibit bands due to tetrahedral and octahedral sites at 598 cm −1 and 445 cm −1 , respectively. The samples were examined by field emission scanning electron microscopy, which showed that they partly comprised hexagonal structures but mostly consisted of irregular structures with rounded edges. Characterization of the elemental contents of the samples by energy-dispersive spectroscopy revealed an increase in the contents of Sm and Nb and a decrease in the contents of Ba and Fe. The magnetic properties of the samples were examined using a vibrating sample magnetometer. The results showed that the saturation magnetization and residual magnetization of the samples decreased slightly with an increase in the contents of the dopants. The coercivity reached its maximum value, namely, 3367.53 Oe, when x = 0.04 and y = 0.08.
研究领域:
材料科学
·
磁学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2021
·
IF 4.641
Jie Li,Feng Gao,Gang Wang,Yan Yang,Yahui Sun,Haokai Su,Xuening Han,Huaiwu Zhang,Qiang Li
Herein, Sm-Ga ions substituted MgCd ferrite (Mg 0.77 Cd 0.23 Fe 2-2x Sm x Ga x O 4 , x = 0.00–0.20) were synthesized via solid state method at low temperature using 2 wt% B 2 O 3 -Bi 2 O 3 -SiO 2 -ZnO glass (BBSZ glass) additive. Sm-Ga substitution did not change the spinel phase formation of ferrite. SEM showed that the grain size first increased and then decreased, while the bulk density displayed the opposite trend and the maximum density was 4.646 g/cm 3 at x = 0.10. Owing to Sm-Ga ions substitution, saturation magnetization ( M s ) first increased, and then decreased, while the coercivity ( H c ) decreased first, and then increased. At x = 0.10, the maximum M s was 25.33 emu/g, and the minimum H c was 28.82 Oe. The real part of magnetic permeability reached a maximum (μ' = 56.02 @x = 0.15) and then dropped down. The ferromagnetic resonance linewidth (at 9.56 GHz) was easily influenced by the Sm-Ga ions substitution, with the minimum value of 251.29 Oe at x = 0.10. Hence, the material has potential for microwave devices applications.
研究领域:
材料科学
·
磁学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Zhiyu Ma,Weijia Guo,Zhenxing Yue
TiO 2 -added Ba 4 (Sm 0.65 Nd 0.35 ) 9.33 Ti 17.75 Al 0.33 O 54 (BSNTA) ceramics were fabricated with a solid-state reaction method. Slight TiO 2 addition increased the dielectric constant ( ε r ) of BSNTA ceramics and brought about a near-zero temperature coefficient of resonant frequency ( τ f ). Sintering in oxygen increased the density of TiO 2 -added BSNTA ceramics and surprisingly concurrently improved the ε r and Q × f value. Thermally stimulated depolarization current (TSDC) measurements indicated that TiO 2 addition introduced oxygen vacancies ( V O .. ) and Ti Ti ' − V O .. defect dipoles and that an oxygen-sufficient sintering atmosphere decreased the concentration of these defects and thus increased Q × f values. From the viewpoint of defect behaviors, this observation offered original insight into the mechanism by which the sintering atmosphere had impacts on the Q × f value of titanate ceramics. Satisfying dielectric properties ( ε r = 79.5, Q × f = 14,840 GHz, τ f = 0 ppm/°C) were attained in oxygen-sintered BSNTA-0.6%TiO 2 ceramics that might be suitable for the manufacture of miniature microwave devices such as filters and antennas.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
X.Z. Zheng,Z.Y. Ye,Y.F. Zhang,L. Yue,Y.F. Lei,W.B. Dai
With the growing concern about energy consumption, white light-emitting diodes( w LEDs), as the fourth generation of lighting sources, are highly scrutinized by researchers. A series of Bi 3+ /Tb 3+ /Sm 3+ (co)doped BaY 2 Si 3 O 10 phosphors were prepared by traditional solid-state method, and the phase purity was analyzed by X-ray diffraction. In this work, Bi 3+ /Tb 3+ /Sm 3+ theoretically occupies the Ba/Y sites, and this conjecture is also proved by spectral analysis. Under near ultraviolet ( n UV) light excitation, Bi 3+ /Tb 3+ /Sm 3+ is respectively used as the blue ( 3 P 1 → 1 S 0 )/green ( 5 D 4 → 7 F j )/red ( 4 G 5/2 → 6 H j ) luminescence center. Due to the energy transfer (ET) efficiency between Bi 3+ /Sm 3+ is not ideal, Tb 3+ is introduced as a bridge to improve the ET efficiency of the whole system to achieve spectral tunability and application in w LEDs. And at different excitation wavelengths, Bi 3+ emits a wide range of blue to cyan light because it occupies two cation sites. We selected a proper excitation wavelength and obtained an emission spectrum covering the whole visible region. The CIE color coordinates (0.3487, 0.3313), the correlated color temperature (CCT, 4773.61 K), quantum efficiency (QE, 47.62 %), and thermal stability ( T 50 = 537 K) of BaY 2 Si 3 O 10 : Bi 3+ /Tb 3+ /Sm 3+ are discussed in depth, Lu 3+ was used instead of Y 3+ to improve the thermal stability of BYS. Its excellent luminescence performance indicates that this phosphor has potential applications in n UV 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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2019
·
IF 4.084
Zuying Feng,Liang Liu,Lingyao Li,Jiahe Chen,Yuhong Liu,Yan Li,Liang Hao,Yan Wu
Three dimensional (3D) printing has attracted much more interest from the research community due to its ability to make complex structures with high resolution and simplified fabrication process. Here we constructed composited electrolyte with certain thickness for the application of low temperature of solid oxide fuel cells. The fabrication of a thin and dense Sm-doped ceria composite electrolyte layers with the thickness about 1200 μm utilizing paraffin-based slurry were investigated. To optimize the assembled cells, 1.7 wt. % glassfiber was introduced and an amazing electrochemical performance was observed. The maximum power density can reach 448 mW/cm 2 , 20% higher than the one without glassfiber and the open-circuit voltage is approximately 1.0 V at 550 °C. It is of great potential for 3D printing technology to develop low temperature solid fuel cells with designed mini-structures.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·Vol. 51
·期 19
·28700-28709
·
IF 5.6
Zhengxiu Ma,Wenwu Cao
Obtaining a large piezoelectric coefficient and high temperature stability simultaneously in piezoelectric ceramics is a formidable challenge. By strategically designing a morphotropic phase boundary (MPB) composition with localized structural heterogeneity, 0.1 Pb(Yb 1/2 Nb 1/2 )O 3 -0.435PbZrO 3 -0.465PbTiO 3 -1mol% Sm ceramic demonstrates outstanding electromechanical performance with d 33 = 585 pC/N, k p = 0.66, T C = 365 °C, and outstanding temperature stability, the piezoelectric coefficient d 33 varies less than 10 % in the temperature range of 25–260 °C, making it a promising candidate for applications in high-temperature transducers and sensors. Our investigations revealed that the enhanced piezoelectricity originates from Sm 3+ induced intensification of relaxor behavior and structural refinement of hierarchical nanodomains, while the high temperature stability is attributed to the larger volume fraction of ferroelectric domains of the T-phase, which provide “pinning” of the nanodomains through the hierarchical domain structure.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Sheng Zhao,Jing Xu,Min Mao,Lingjiao Li,Xuanhao Li
A dye-sensitive photocatalytic H 2 evolution reaction (HER) system with photogenerated carrier directed conduction was constructed. The protonated g-C 3 N 4 combines with the sheet-like Co MOF to form a 2D/2D heterojunction via electrostatic self-assembly. The protonated g-C 3 N 4 and 2D Co-MOF directionally adsorb Eosin Y (EY) and triethanolamine (TEOA) molecules through hydrogen bond and complexation to achieve a whole photocatalytic system. The integral structure effectively facilitates the utilization of dye sensitizer and hole sacrificial agent to achieve the effective and stable photocatalytic H 2 evolution capacity. The photocatalytic hydrogen evolution rate of g-C 3 N 4 after protonation is 1.88 times as high as that of the original g-C 3 N 4 . On the basis of 2D/2D heterojunction, Co MOF is doped with rare earth element Sm. The 4f electrons and the difference valences (Sm 3+ and Co 2+ ) further suppress the reorganization of photogenerated excitons to achieve highly efficient photocatalytic HER. The directional coupling of sensitizer and electron sacrificial agent combined with rare earth element doping makes the photocatalytic HER rate of the composite material reached 73.42 μmol . h −1 within 5 h under simulated sunlight.
研究领域:
材料科学
·
光化学
·
能源科学
✓ 已验证
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2019
·
IF 2.781
Hong Lei,Tingting Liu,Lei Xu
SiO 2 abrasive is one of the most effective abrasives used in chemical mechanical polishing (CMP) due to its uniform size, good dispersibility and good chemical reactivity. In this paper, a series of novel Sm-doped colloidal SiO 2 composite abrasives were synthesized by seed-induced growth method. The composite abrasives were characterized by using scanning electron microscopy, time-of-flight secondary ion mass spectrometry analysis (TOF-SIMS) and X-ray photoelectron spectroscopy (XPS). The structure of the composite abrasive is core-shell type with silica as a core and a coated growth layer (including SiO 2 , Sm 2 Si 2 O 7 and Sm(OH) 3 as shell via chemical bonds and hydrogen bonds . The CMP properties of the composite abrasives on sapphire substrates were further studied and the results show that the Sm-doped colloidal SiO 2 composite abrasives give lower polished surface roughness (Ra) and higher MRR than that of the pure colloidal SiO 2 abrasive under the same polishing conditions. By TOF-SIMS and XPS analyses on the polished slurries, the acting mechanisms of Sm-doped colloidal SiO 2 composite abrasives on sapphire were explored also.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2025
·
IF 6.2
Weijia Guo,Yutian Lu,Chongyang Zhang,Zhenxing Yue
Low-loss (high- Q × f , where Q = 1/tan δ ) dielectric ceramics can help achieve efficient microwave signal transmission and reduce heat generation. In the traditional Ca-Ln-Ti-O perovskite system (where Ln = rare earth) with the general formula of Ca 1– x Ln 2 x /3 TiO 3 (CST x ), the sharp decline in the Q × f value when x > 0.5 remains unexplained, posing a challenge for designing low-loss ceramics. In this study, CST x ceramics ( x ≤ 0.7) are synthesized via the solid-state reaction method, with a focus on their structure, defects, and broadband dielectric properties. A significant discrepancy between the Q × f values in the microwave and terahertz bands is found when x ≥ 0.6, suggesting the presence of additional loss mechanisms in the microwave band beyond ion displacement depolarization. Meanwhile, the low-frequency dielectric spectra show a weak dielectric relaxation in the low-temperature region, attributed to the partially ordered A -site vacancies. Therefore, this relaxation can act on the microwave frequency band at room temperature, resulting in a sharp decline in Q × f values. Such low-frequency and low-temperature dielectric relaxation should not be ignored in the research of microwave dielectric ceramics. These findings provide a crucial theoretical reference for developing low-loss microwave dielectric 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
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Yuanhao Luo,Ling Lin,Pingya Luo,Yongjun Guo,Shuixiang Xie,Meirong Wang,Guixia Xiong,Han Gu
High temperatures degrade drilling fluid performance and endanger drilling safety when drilling deep and ultra-deep wells. The development of a new high-temperature drilling fluid additive to maintain drilling fluid performance in high-temperature environments is critical. A polymer nanocomposite (ADA@SM) was synthesized from the monomers styrene (St), methyl methacrylate (MMA), acrylamide (AM), 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS), and diallyldimethylammonium chloride (DMDAAC) through a free-radical copolymerization reaction. Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance ( 1 H NMR) were used to characterize the structure of ADA@SM, and transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to characterize the microstructure of ADA@SM, indicating that it had a "star-net" structure. TGA analysis showed that the thermal decomposition temperature of ADA@SM was above 274 °C. The rheological and filtration properties of drilling fluids with ADA@SM were studied before and after aging at high temperatures (150–240 °C). The rheological model of the drilling fluid containing 2.5 wt% ADA@SM was found to be consistent with the Herschel-Buckley model. After aging at 220 °C, the filtration loss for API and HTHP was 8.4 mL and 29.8 mL, respectively. Using particle size analysis and zeta potential analysis, ADA@SM produced a drilling fluid with good particle size distribution and colloidal stability in high temperature environments . SEM analysis showed that ADA@SM adsorbed on the surface of the bentonite particles, which improved the compactness of the filter cake. The relative molecular weight (Mn) of ADA@SM decreased from 59671 to 5908 after degradation at high temperatures, and ADA@SM released polymer nanospheres , which effectively reduced the filtration loss of the drilling fluid.
研究领域:
材料科学
·
石油工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Ting Wang,X.-L. Wang,S.-H. Song,Qing Ma
Multiferroic Nd/Sm-doped BiFeO 3 ceramics synthesized at 700 °C by spark plasma sintering in conjunction with sol-gel precursor powders are investigated by X-ray diffraction, scanning electron microscopy, dielectric , ferroelectric and magnetic measurements. With the doping content of Nd/Sm beyond 10 mol%, the crystal structure changes from R 3 c to coexistence of Pbam and R 3 c . It is also revealed that the grain size for all samples greatly decreases and the dielectric, ferroelectric and magnetic properties are obviously improved with Nd/Sm doping. The optimized remanent polarization are about 1.451 μC/cm 2 and 3.448 μC/cm 2 for the 10 mol% Nd-doped and 15 mol% Sm-doped BiFeO 3 ceramics, respectively. Because of the reduced concentration of oxygen vacancies , the leakage current density of Nd/Sm-doped ceramics decreases more than two orders of magnitude compared to the pure BiFeO 3 sample. The maximum remanent magnetization for the Sm-doped ceramics is approximately 0.279 emu/g, which is higher than that for the Nd-doped samples (0.263 emu/g).
研究领域:
材料科学
·
凝聚态物理
·
无机化学
✓ 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）