TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2024
·
IF 4.7
Xiao-qing LU,Ai-min LIU,Feng-guo LIU,Xian-wei HU,Zhong-ning SHI
The feasibility and reaction mechanism of NdFeB film electrodeposition in 1,3-dimethyl-2-imidazolidinone (DMI)−LiNO 3 ionic liquid analogs at room temperature were investigated. Cyclic voltammetry indicated that the reduction peak at −1.83 V (vs Ag) was related to the reduction of Fe(II) to Fe, while the reduction peak at −2.01 V (vs Ag) was related to the reduction of B(III) to B. The electrochemical reduction reaction of Fe(II) and B(III) were irreversible processes controlled by diffusion, and the diffusion coefficients of Fe(II) and B(III) at 313 K were 3.03×10 −6 and 6.74×10 −7 cm 2 /s, respectively. In addition, XRD analysis suggested that the product obtained by the electrodeposition in DMI−LiNO 3 −Nd(CF 3 SO 3 ) 3 −FeCl 2 −H 3 BO 3 ionic liquid analogs for 2 h on the Al substrate contained NdFe 3 B 3 . SEM and EDS analysis showed that Nd, Fe, and B in the cathode product were uniformly distributed. XPS analysis revealed that the mass fractions of Nd, Fe, and B on the W substrate were 27.44%, 27.90%, and 7.51%, respectively.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2019
·Vol. 166
·期 2
·D65
·
IF 3.12
Min Li,Ying Li,Zhaowen Wang
The electrochemical reduction of zirconium oxide in a molten salt of 2.4NaF·AlF3 (molar ratio = 2.4) was studied at 1273 K. Cyclic voltammetry results show that Zr(IV) ions are first reduced to an intermediate valence and, then, are co-deposited with aluminum to form an Al-Zr alloy. Potentiostatic electrolysis experiments were carried out at different potentials (−0.95 and −1.25 V) and at 1273 K, and the electrolysis products were characterized using SEM-EDS and XRD. The XRD analysis confirms that a mixture of cryolite molten salt and ZrO2 was electrodeposited at −0.95 V, while aluminum and Al3Zr were electrodeposited at −1.25 V. The SEM analysis shows that the aluminum and Al3Zr were in two different phases.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
·
2025
·
IF 5
Hao Fu,Xuesong Jiang,Xiaotian Chen,Zhenyi Hu,Jifei Sun,Zongrong Zhou,Ling Wang,Boyuan Ban,Jian Chen
Al is one of the most difficult to remove impurities from quartz. Even with HF, only a limited removal efficiency was demonstrated. This study proposes a novel and environmentally friendly strategy centered on a combined process of ball milling, Na 2 CO 3 roasting, fluorine-free acid leaching, and chlorination roasting. The core innovation lies in the strategic induction of a consecutive and reversible phase transformation cycle (α-quartz → cristobalite → α-quartz), which serves as an internal grain refiner to achieve continuous microstructure refinement, thereby constructing abundant fast pathways for impurity migration. A comprehensive XRD analysis was introduced to observe the microstructure evolution. The results indicate that Na 2 CO 3 promotes the phase transformation from α-quartz into cristobalite at a relatively low temperature, while chlorination roasting facilitates the reverse transformation back to α-quartz. It revealed that these two distinct phase transformations not only disrupt the crystal integrity but also lead to significant microstructure refinement accompanied by abundant lattice defects. Through these defects, Al impurities rapidly migrate to the quartz particle surface, where they react with the acid solution and HCl gas, enabling efficient removal. Under the optimal process, the Al removal rate reached 90.5 %, the total impurity removal rate attained 98 %, and the quartz purity increased from 99.683 wt% to 99.994 wt%. This work highlights the crucial role of reversible phase transformation-induced grain refinement as an efficient strategy for lattice impurity removal, offering a green and high-performance alternative to HF-based purification with demonstrated advantages in environmental safety, energy efficiency, and product yield.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2021
·
IF 3.498
Yaxin Feng,Guilin Wei,Yi Liu,Wenhong Han,Yan Chen,Runjie Sun,Lin Peng,Meihua Ma,Yu Zhang,Zhentao Zhang,Xirui Lu
The immobilization of iodine waste is a challenge in the field of nuclear waste . In this work, iodine waste (silver-coated silica gel with different iodine loadings) was immobilized at low-sintering temperatures (500, 550, and 600 °C). XRD represented that the crystallized phases of the sintered matrix consist of AgI and B 2 O 3 . The crystallization behavior of boron can be found as the sintering temperature increased from 500 °C to 600 °C. FT-IR results proved that in the process of crystallization, part of the microstructure related to B–O stretching transformed from [BO 4 ] to [BO 3 ] units, which benefits low-temperature iodine waste immobilization due to the bonding energy of [BO 3 ] is higher than that of [BO 4 ]. Our work reveals the B-related microstructure transition in low-temperature immobilization iodine waste.
研究领域:
核废物处理
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材料科学
·
无机化学
·
放射化学
·
环境工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 105
·86620-86624
·
IF 3.84
Tao Wang,Huiping Zhang,Ying Yan
A novel porous zeolite beta coating/PSSF composite was prepared by secondary growth method in fluoride media. The morphology of zeolite beta coating/PSSF composite was characterized by SEM and the structural and textual properties of composite were characterized by XRD and N2 adsorption/desorption isotherms on ASAP 2020, respectively. The thermal stability of composite was analyzed by thermogravimetry (TG) and differential scanning calorimetry (DSC). The results indicated that well-intergrown and continuous zeolite beta coating with highly crystallinity were successfully synthesized on the surface of paper-like stainless steel fibers support. The structures of zeolite beta coating/PSSF composite were three-dimensional network with large void volume and majority of microporous structure. The thickness of zeolite beta coating on stainless steel fibers is approximate 2 μm. The specific surface area (SBET) and the total pore volume of composite were 118 m2 g−1 and 0.067 cm3 g−1, respectively. The composite was stable at temperature up to 650 °C.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2022
·
IF 4.598
Mingjun Lu,Rongting Guo,Wei Li,Yiju Lv,Fushun Tang,Weiyi Feng,Zheng Liu,Guo-Cheng Han,Zhihua Zhan
The interfacial characterization of the cathode material Na 2 FePO 4 F with carbon capping material Na 2 FePO 4 F@C taking bagasse as the carbon source is reported. Both the higher-capacity Na 2 FePO 4 F@C material (93 mAh/g) and lower-capacity Na 2 FePO 4 F material (10 mAh/g) showed different degrees of capacity decay during cycling. The rupture and spontaneous repair process of the solid electrolyte interface (SEI) film resulting in increased impedance and blocked charge transfer, as well as irreversible changes in the surface microstructure of the electrode material after cycling, which are responsible for the decrease in capacity. The XRD and FTIR results before and after cycling shown that the characteristic peaks of the carbon coated material Na 2 FePO 4 F@C and raw material Na 2 FePO 4 F were consistent, indicated that their functional groups and crystalline structures are not the main causes of capacity decay at low cycling times (within 50 cycles).
研究领域:
电化学
·
材料科学
·
能源存储
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电池技术
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界面化学
·
无机非金属材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2024
·Vol. 35
·期 1
·1-8
·
IF 2.8
Ma Jianli,Zhang Yu,Chen Chen,She Yubin
An efficient reaction sintering process is engaged to synthesize a series of non-stoichiometric Li 2(1+ x ) Mg 3 TiO 6 ( x = 0.01, 0.02, 0.03, 0.04) microwave dielectric ceramics. The single phase of Li 2 Mg 3 TiO 6 with rock-salt structure is accurately recognized by XRD. Pores left on the surface and inside the sample can be clearly observed from SEM pictures. Excessive Li + affects the local charge distribution, which influences the response of the dielectric material to the electric field. The pores are not the same medium as the matrix material, and the signal is refracted and scattered when it passes through the pores. Refractions and scatterings increase the signal transmission distance and also increase the transmission loss. These residual Li + and pores eventually affect the dielectric properties as well. Finally, at x = 0.02 and a sintering temperature of 1260 °C, the ceramic samples showed good dielectric properties: ε r = 10.983, Q×f = 107,367 GHz and τ f = − 24.2 ppm/°C.
研究领域:
材料科学
·
陶瓷材料
·
微波介质
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固态物理
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X射线衍射
·
扫描电子显微镜
✓ 已验证
DOI
高影响因子
Journal of Nano Research
·
2022
·
IF 1.78
Rusul Mohammed Abdallah,Raad M.S. Al-Haddad
There are many methods for synthesizing magnetite nanoparticles. Most methods take a long time, and the result is undesirable. In this paper a green method was used to synthesize nanoparticles because it takes a short time and is both straightforward and eco-friendly. It is done by adding : =1:2 molar ratio solution with different amounts of extract and different amounts of NaOH solution for 20 min at different temperatures, in hotplate stirrers, to control their relative size. UV-Vis spectroscopy, vibrating sample magnetometer technique (VSM), transmission electron microscopy (TEM), and X-ray diffraction (XRD) were used to characterize the magnetite nanoparticles. The result confirms that the changes in amounts of NaOH and extract led to a change in the pH of a solution and that the increase in amounts of the extract caused the low addition of NaOH. These changes influenced the process of synthesis and characterization. The Uv-vis analysis confirms that the surface plasmon resonance had a highly visible brad peak in the 290–460 nm range, as well as a peak shift to shorter wavelengths (blue shift) with a pH change and a peak shift to longer wavelengths (red shift) with a temperature change. TEM imaging confirms that all the synthesized had a spherical shape with size changed according to a parameter change of within 40–9 nm. Magnetic analysis showed the magnetite nanoparticles synthesized have smaller sizes and are superparamagnetic with the influence of particle size on the magnetic properties, including Hc, Ms, and Mr.
研究领域:
材料科学
·
纳米技术
·
化学
·
物理学
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2021
·Vol. 127
·期 10
·1-9
·
IF 2.584
Zhang Yu,Cao Ping,Lin Wei,Liu Qiang,Chen Ziyuan,Cao Jun,Yang Guannan,Cui Chengqiang
In this paper, a mixed sintering accelerator of colophony and cetyltrimethyl ammonium bromide (CTAB) was developed to improve the sintering properties of Cu nanoparticles (NPs) paste. With the synergy effect of the mixed sintering accelerator, Cu NPs paste could be well sintered at 260 °C for 30 min under a pressure of 2 MPa, and the shear strength was greatly improved from 15 to 33 MPa. The fracture morphology of the Cu NPs joint transformed from brittle interface failure features to ductile dimple features, and the porosity in the sintered layer was significantly reduced. XRD analysis further confirmed that the synergy of colophony and CTAB could effectively remove the oxides in the Cu NPs paste during sintering, and thereby improve the sintering properties. This work can provide an applicable approach to improve the sintering properties of metal NPs and help to understand the synergy effect of sintering accelerators on the bonding behaviors of metal nanoparticles at low temperatures. Graphic abstract
研究领域:
材料科学
·
纳米技术
·
化学工程
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2024
·
IF 5.3
Jinning Wang,Qiufeng Shi,Konstantin V. Ivanovskikh,Lei Wang,Jianwei Qiao,Haijie Guo,Ping Huang
A series of Mn 4+ -doped NaSr 10 Y 5 W 4 O 30 (NSYWO) phosphors have been successfully synthesized and further characterized to estimate their potentials for application as a far-red emitting component of pc-LED. An XRD analysis and crystal structure refinement have been carried out to characterize its quality. The doping concentration and temperature (80–500 K) dependent luminescence properties as well as decay kinetics have been studied and analyzed. It has been found that Mn 4+ substitutes for W 6+ sites resulting in far-red emission at 688 nm. The temperature quenching is attributed to thermal activation of an electron from Mn 4+ 2 E g to 4 A 2g state via crossover, yielding an activation energy of 0.35 eV. Furthermore, to assess practical application of the novel phosphor, a blue-emitting LED chip combined with NSYWO: 0.8 mol% Mn 4+ has been packaged. The light from both the blue-emitting LED chip and NSYWO: Mn 4+ phosphor was shown to be effectively utilized, revealing a good promise for application of the phosphor in the field of plant growth lighting.
研究领域:
材料科学
·
光电
·
植物生物学
·
光子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）