Journal of Superconductivity and Novel Magnetism
·
2022
·Vol. 36
·期 1
·327-341
·
IF 1.675
Li Pengwei,Li Jie,Wang Yonglun,Yao Kai,Shan Shuo,Suo Xing,Ma Saisai
Praseodymium (Pr)–aluminum (Al)-co-doped M-type barium ferrite with Ba 0.85 Pr 0.15 Fe 12-x Al x O 19 ( x = 0.0–1.0) was prepared by combining solid-phase sintering with high-energy ball milling. The samples were characterized using a thermogravimetric analyzer, X-ray diffractometer, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and vibrating sample magnetometer. Thermogravimetric analysis indicated that M-type barium ferrite was formed at 1250 °C. X-ray diffraction patterns showed that Al doping did not destroy the crystal structure of barium ferrite. Field emission scanning electron microscopy showed that the samples had a hexagonal crystal structure. The wave numbers of Fourier transform infrared spectroscopy in the 597–607 and 452–459 cm −1 bands represent tetrahedral and octahedral clusters, respectively. With the increase in the amount of Al doping ( x ) from 0.0 to 1.0, the saturation magnetization ( M s ) and residual magnetization ( M r ) decreased continuously, and the magnetic anisotropy field ( H a ) and coercivity ( H c ) increased significantly.
研究领域:
材料科学
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无机化学
·
磁性材料
·
固体物理
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2020
·
IF 2.726
Xiaofen Wang,Jiang Ma,Xirui Lu,Zhiwei Fang,Lingshuang Li,Linyan Li,Yushan Yang
Hollandite ceramics are considered as a promising host matrix for cesium immobilization. In the paper, [Cs x Ba y ][Fe 3+ 2 y + x Ti 4+ 8-2 y - x ]O 16 (0.3 ≤ x , y ≤ 0.75) ceramics were synthesized by solid-state reaction method using 133 Cs and 133 Ba as the substitutes for radioactive Cs and its daughter product Ba. It was found that the as-prepared (Cs,Ba)-hollandite solid solution shows a tetragonal structure ( I 4/m) with >90% crystallinity and good Cs retention at 1250 °C. Moreover, the normalized release rates of Cs and Ba are in the order of 10 −3 g m −2 d −1 for 28 days, exhibiting excellent aqueous durability.
研究领域:
材料科学
·
核废物管理
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2014
·Vol. 97
·期 6
·1797-1801
·
IF 2.428
Xuechen Huang,Hua Hao,Shujun Zhang,Hanxing Liu,Wenqin Zhang,Qi Xu,Minghe Cao
(1− x )BaTiO 3 – x BiYO 3 [(1− x )BT– x BY] polycrystalline ceramics were prepared by solid-state reaction method. The ceramics are in tetragonal phase when x ≤ 0.04, transform to pseudocubic at x ≥ 0.06, showing a classic ferroelectric to relaxor transition at x = 0.06, where the phase transition temperature was found to shift to higher temperature with increasing frequency. The dielectric permittivity peaks were analyzed by the modified Curie–Weiss law. Both parameters ΔT diffuse and ΔT relaxor were found to increase with increasing BY content, demonstrating a stronger relaxor characteristic.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Superconductivity and Novel Magnetism
·
2022
·Vol. 35
·期 9
·2473-2484
·
IF 1.675
Li Pengwei,Li Jie,Zhang Wenhao,Wang Yonglun,Yao Kai
Pr-doped M-type barium ferrite with a composition of Ba 1− x Pr x Fe 12 O 19 (0.00 < x < 0.25) was prepared via solid-state sintering combined with high-energy ball milling. The structures, spectra, morphologies, and magnetic properties of Pr 3+ -substituted Ba hexaferrites were analyzed herein. Under high-energy ball milling, the material produces crystal vacancy defects for elemental doping. The X-ray diffraction results showed that the hexagonal crystal structure was affected when the Pr content ( x ) was > 0.20. The GSAS refinement results show that the synthesized samples were good. The scanning electron microscopy results and Fourier transform infrared (FT-IR) spectra of the tetrahedral and octahedral sites (FT-IR result of the Fe–O bond = 601 and 448 cm −1 peaks, respectively) of the prepared material proved the formation of a hexagonal crystal structure. The magnetic properties of the samples were measured using a vibrating sample magnetometer at room temperature, and the obtained results demonstrated that the coercivity increased with an increase in the doping amount (from 3815.03 at x = 0 to 4600.56 kOe at x = 0.25). At the same time, the saturation magnetization maintained its high value (> 72.568 emu/g), which is beneficial for preparing permanent magnets.
研究领域:
材料科学
·
磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
·
2015
·
IF 1.97
Pingyuan Meng,Kun Xiong,Kui Ju,Shengnan Li,Guangliang Xu
To achieve stronger microwave attenuation and larger bandwidth in electromagnetic absorber, the nickel ions (Ni 2+ ) and manganese ions (Mn 2+ ) were employed to partially replace the cobalt ions (Co 2+ ) in BaCoTiFe 10 O 19 , and the doped barium hexaferrite (Ba(MnNi) 0.2 Co 0.6 TiFe 10 O 19 and Ba(MnNi) 0.25 Co 0.5 TiFe 10 O 19 ) powders were synthesized via the sol–gel combustion method. Subsequently, the microwave absorbing composites were prepared by mixing the ferrite powders with the paraffin. The X-ray diffraction (XRD) patterns of the doped ferrites confirmed the formation of the M-type barium ferrite , and no other types of barium ferrite could be found. Based on the electromagnetic parameters measured by the vector net-analyzer, it was found that the composite (Ba(MnNi) 0.2 Co 0.6 TiFe 10 O 19 ) possessed a minimum reflection loss of −52.8 dB at 13.4 GHz with a matching thickness of 1.8 mm and the bandwidth below −15 dB was 5.8 GHz. Moreover, the maximum attenuation of Ba(MnNi) 0.25 Co 0.5 TiFe 10 O 19 could reach −69 dB when its thickness was 1.8 mm, and also the bandwidth less than −20 dB was ranging from 13.2 GHz to 18 GHz. Thus, Ba(MnNi) 0.2 Co 0.6 TiFe 10 O 19 and Ba(MnNi) 0.25 Co 0.5 TiFe 10 O 19 could be the good microwave absorbers, which have great potentials to be applied in the high frequency fields of the microwave absorbing materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2016
·
IF 3.014
Longwen Wu,Xiaohui Wang,Longtu Li
Core-shell BaTiO 3 @BiScO 3 (BT@BS) particles were fabricated via a facile sol-precipitation method, with which bulk ceramics were prepared via conventional sintering. Pure perovskite phases of the BT@BS ceramics were confirmed by XRD patterns. Grain sizes and DC conductivities of the BT@BS ceramics are suppressed in comparison with pure BT. Dielectric-temperature measurements show that with the addition of BS, the tetragonal-orthorhombic and orthorhombic-rhombohedral peaks sequentially disappear with gradual broadening and dispersion of Curie peaks. Wide and flat dielectric-temperature plateau is achieved in the ceramic with 3 mol% BS coatings, which is due to the formation of local compositionally graded structure from the modulated diffusion of Bi and Sc. Weakened polarization nonlinearity and reduced hysteresis are achieved in the BT@BS ceramics, which contribute to enhanced energy storage capability. This work provides a generic avenue for fabricating temperature-stabilized dielectrics with improved energy storage density.
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
Small
·
2016
·Vol. 13
·期 6
·1602055
·
IF 8.315
Ding Zhou,Yuechen Zhai,Songnan Qu,Di Li,Pengtao Jing,Wenyu Ji,Dezhen Shen,Andrey L. Rogach
Carbon nanodots (CNDs)@BaSO 4 hybrid phosphors are fabricated in an easy and low-cost process by sequentially assembling Ba 2+ and SO 4 2− ions onto the surface of carbon nanodots through electrostatic attraction. CNDs act as the nucleus to attract these reactive ions and provide the luminescent centers in the hybrid phosphors. This strategy is versatile for a variety of negatively charged CNDs with different emission colors. The advantage of the resultant hybrid phosphors is that their luminescence exhibits excellent thermal and photostability, as well as remarkable resistance to strong acid/alkali and common organic solvents. These merits allow for the fabrication of CNDs-based light-emitting diodes using the CNDs@BaSO 4 hybrid phosphors as a color conversion layer.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Minerals
·
2018
·Vol. 8
·期 7
·296
·
IF 1.835
Jing Ouyang,Dawei Mu,Yi Zhang,Huaming Yang,Steven L. Suib
Barium carbonate (BaCO3) materials with the controllable morphology of nanoparticles were selectively loaded into the lumen halloysite nanotubes (abbreviated as Hal) by a urease assisted catalytic implementation strategy. The Hal mineral was pre-treated through leaching by hydrochloric acid (abbreviated as A-Hal), resulting in increased defect sites and zeta potential. The negatively charged urease was loaded inside the positively charged A-Hal lumen, and then through the decomposition of urea catalyzed by urease to produce carbonate ions and ammonia. When Ba2+diffused in, BaCO3particles were selectively synthesized in the lumen of A-Hal, the pore channels of A-Hal effectively controlled the growth and aggregation of BaCO3nanocrystals and their geometrical morphology. The obtained BaCO3/A-Hal-T was characterized by transmission electron microscopy, Fourier transformation infrared spectroscopy and X-ray diffraction, differential scanning calorimetry-thermogravimetry (DSC-TG). The BaCO3/A-Hal-T may provide a candidate for potential applications.Keywords:halloysite;urease;barium carbonate;selective decoration;nanoreactors
研究领域:
材料科学
·
生物催化
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2015
·
IF 4.772
Yanyan Fan,Xingyi Huang,Guanyao Wang,Pingkai Jiang
Flexible high-dielectric-constant (high-κ) nanocomposite dielectrics comprising polymer matrix and ceramic nanoparticles have important applications in the fields of electrical insulation and energy storage. However, most of the flexible high-κ nanocomposites are fabricated by using nonbiodegradable polymers as matrixes, which may not meet the increasing demands of society for environmental sustainability. In this study, using biodegradable polylactic acid (PLA) as a matrix and core–shell structured BaTiO3 (BT) nanoparticles as high-κ filler, we report the preparation and structure–property relationship of environmentally friendly flexible high-κ polymer nanocomposites. Two types of core–shell structured high-κ nanoparticles [polydopamine-encapsulated BT (BT@PDA) and PLA-encapsulated BT@PDA (BT@PDA@PLA)] as well as as-prepared BT nanoparticles were used as filler of the PLA-based high-κ nanocomposites. It was found that, compared with the as-prepared BT nanocomposites, the core–shell nanoparticle-based composites show enhanced dielectric constant, suppressed dielectric loss tangent, and enhanced breakdown strength. In addition, the BT@PDA@PLA nanocomposites have much higher dielectric constant and energy density. The nanoparticle–PLA compatibility and its influence on the dielectric and energy storage properties of the nanocomposites were also investigated. Because the polymer matrix is environmentally friendly and the preparation process of the core–shell nanoparticles is facile and nontoxic, the nanocomposites reported here may be used in the next generation of environmentally friendly high-performance energy storage devices.
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
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2020
·Vol. 126
·期 4
·1-9
·
IF 1.81
Qian Haoyu,Zhu Guisheng,Xu Huarui,Zhang Xiuyun,Zhao Yunyun,Yan Dongliang,Hong Xianyong,Han Yin,Fu Zhenxiao,Ta Shiwo,Yu Aibing
Tetragonal-phase BaTiO 3 powders of particle size 370 nm were synthesized by microwave sintering at 850 °C. The raw materials were BaCO 3 , TiO 2 , and alanine. SiC microspheres were used as microwave conductors. The effects of the holding time, sintering aids, and SiC addition on the preparation of BaTiO 3 were investigated. The results indicate that the addition of SiC as a microwave acceptor leads to formation of microwave micro-regions. This enables uniform heating of the raw materials and decreases the calcination temperature needed to obtain BaTiO 3 . Alanine coordinates with Ba, and this loosens the metal–CO 3 bond and promotes separation of CO 2 , decreases the BaCO 3 decomposition temperature, and provides a higher nucleation site density. It gives an idea about the microwave solid-state synthesis of BaTiO 3 powder.
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
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Zeyun Wu,Yiyang Zhang,Zuoqing Liu,Haorui Ma,Xing Jin,Guangming Yang,Yixiang Shi,Zongping Shao,Shuiqing Li
Perovskite-type proton-conducting materials, such as BaCe0.7Zr0.1Y0.1Yb0.1O3−δ (BCZYYb), are very attractive for the next-generation equipment of electrochemical energy conversion and storage owing to their excellent conductivity in the intermediate-temperature range (300–750 °C), as well as good thermo-chemical stability, coking resistance, and sulfur tolerance. However, the lack of a reliable and cost-effective synthesis method for such multi-component co-doping oxides limits their large-scale application. In this study, for the first time, we successfully synthesize BCZYYb electrolyte nanopowders by using a rapid, scalable flame-based gas-phase synthesis method with two different barium precursors Ba(NO3)2 and Ba(CH3COO)2, named as BCZYYb (N) and BCZYYb (CA). The as-synthesized nanoparticles exhibit good crystallinity of the pure orthorhombic perovskite BCZYYb phase. BCZYYb (CA) shows more uniform doping with the element ratio of 1:0.74:0.12:0.08:0.1, which is very close to the theoretical value. The shrinkage and surface SEM (scanning electron microscope) results indicate that the flame-made powders have superior sinterability compared to the sol–gel-made powders because of the smaller primary particle size (∼20 nm). Electrochemical impedance spectroscopy tests show that BCZYYb (CA) sintered at 1450 °C has the highest protonic conductivity of 1.31 × 10–2 S cm–1 in wet H2 when operating at 600 °C and still maintains a high-level conductivity of 1.19 × 10–2 S cm–1 even when the sintering temperature is reduced to 1350 °C, which is mainly attributed to uniform doping and good sinterability. The activation energy for the conductivity of BCZYYb (CA) is also significantly lower than that of conventional electrolytes, which suggests much better conductivity in the intermediate (∼600 °C) and even lower operating temperature. The excellent conductivity performance combined with the high-throughput production capability makes the swirling spray flame a promising synthesis method for promoting the BCZYYb electrolytes from lab to industrial-scale solid oxide fuel cells.
研究领域:
材料科学
·
电化学
·
能源转换与存储
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2024
·
IF 5.3
Kang Du,Zheyu Liu,Changzhi Yin,Yiyang Cai,Mengdie Zhou,Tailai Wen,Wei Zhu,Cai Zhou,Weijia Han,Shengxiang Wang,Wen Lei
Novel Ba 2 RE 2 Si 4 O 13 ( RE = La, Nd, Sm, Eu, Gd, Ho, Er and Yb) ceramics were prepared by traditional solid reaction methods. The phase compositions of Ba 2 RE 2 Si 4 O 13 ceramics were explored. The triclinic structure with P 1 ¯ space group of Ba 2 RE 2 Si 4 O 13 ceramics was confirmed by TEM and Rietveld refinement analyses, and the decrease in the ionic radius of RE 3+ induced the phase transition from low symmetry (triclinic) to high symmetry (monoclinic) between Ba 2 Sm 2 Si 4 O 13 and Ba 2 Eu 2 Si 4 O 13 . ε r-exp of the Ba 2 RE 2 Si 4 O 13 ceramics was significantly affected by ionic polarisability. The ‘rattling and compressing effects’ of cations also affected the ε r-exp of Ba 2 RE 2 Si 4 O 13 ceramics. The intrinsic dielectric loss of Ba 2 RE 2 Si 4 O 13 ceramics were evaluated by the far-IR reflectivity spectrum, and high Q × f values of the Ba 2 Nd 2 Si 4 O 13 and Ba 2 Eu 2 Si 4 O 13 ceramics were attributed to their large total lattice energy and activation energy. The average bond valence of RE 3+ played an important role in controlling the τ f values of the Ba 2 RE 2 Si 4 O 13 single-phase ceramics, and the high average bond valence of RE 3+ corresponded with the small negative τ f values. Great microwave dielectric properties ( ε r = 11.52, Q × f = 33,600 GHz at 11.80 GHz and τ f = ‒25.6 ppm/ °C) were obtained in the Ba 2 Nd 2 Si 4 O 13 single-phase ceramic.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）