Article
Materials Science, Multidisciplinary
Yu-Yang Bian, Shu-Qiang Guo, Yu-Ling Xu, Kai Tang, Xiong-Gang Lu, Wei-Zhong Ding
Summary: A high-temperature pyrometallurgical process was developed to recover valuable rare earth elements from Nd-Fe-B permanent magnet scraps. By pulverizing and oxidizing the magnet scraps, the rare earth elements were extracted as oxides while separating Fe and B as metal phase. Temperature and reaction time were found to be crucial for improving the purity of rare earth oxides.
Article
Chemistry, Physical
Mario Schoenfeldt, Urban Rohrmann, Philipp Schreyer, Mahmudul Hasan, Konrad Opelt, Juergen Gassmann, Anke Weidenkaff, Oliver Gutfleisch
Summary: The effects of multiple recycling of scrap magnets from magnetic resonance tomography devices were investigated. The changes in different material properties were studied, including chemical composition, impurity content, particle size, magnetic properties, microstructure, and degree of alignment. The recycling process led to a decrease in texture, orientation, and magnetic properties, as well as an increase in impurities and particle size. The addition of Nd hydride improved the properties, with 4 wt.% Nd hydride fully restoring the density of the recycled magnets. The recycled magnets met the specification of primary magnets and outperformed them in terms of sustainability and production cost reduction.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Engineering, Environmental
Wei-da Wang, Tan Wang, Zhen-bo Sun, Yan-xin Bo, Chang-xiong Zou, Zhe Wang, Chun-li Zheng
Summary: This study aimed to solidify rare earth tailings using microbial-induced calcium carbonate precipitation (MICP) technique. The results showed that MICP can effectively reduce the leaching of heavy metals and radionuclides, while maintaining the potential reuse of the tailings.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2023)
Article
Multidisciplinary Sciences
Aliaa G. Mohamed, Hussein A. Elsayed, Ahmed Mehaney, Arafa H. Aly, Walied Sabra
Summary: We theoretically demonstrated and explored the transmittance characteristics of a one-dimensional binary photonic crystal composed of metamaterial and nanocomposite layers. By optimizing the optical parameters of the nanocomposite layer, this research could lead to improved performance of photonic crystal circuits and devices.
SCIENTIFIC REPORTS
(2022)
Article
Engineering, Chemical
Iryna Makarava, Aliaksandr Kasach, Dzmitry Kharytonau, Irina Kurilo, Markku Laatikainen, Eveliina Repo
Summary: This study investigates the development of an effective technology for recovering critical rare-earth elements (REEs) from end-of-life permanent magnets. Chemical and electrochemical leaching of NdCeFeB magnets in sulfuric acid with varying concentrations of oxalic acid were examined. It was found that efficient separation of REEs can be achieved at specific concentrations of oxalic acid, and the leaching rate is substantially higher in electrochemical leaching compared to chemical leaching.
MINERALS ENGINEERING
(2022)
Article
Materials Science, Multidisciplinary
Chih-Chieh Mo, Chih-Cheng Kuan, Yung-Hsiang Wang, Yu-Sheng Lu, Tsung-Wei Chang, Wei-Yu Liao, Te-Hua Fang, Mi-Ching Tsai, Ching-Chien Huang
Summary: This study demonstrates an innovative and effective method for recycling waste NdFeB magnets by preparing recycled sintered NdFeB magnets on a large scale. By adding NdCoGa alloy to waste wind turbine NdFeB magnets, the proposed process restores the magnetic properties of the recycled magnets to the level of the original waste magnets, enhances their corrosion resistance, and reduces the cost of magnet remanufacturing.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2023)
Article
Physics, Applied
Jean-Marie Poumirol, Adrien Bercher, Tetiana Slipchenko, Ivan Maggio-Aprile, Christoph Renner, Alexey B. Kuzmenko
Summary: The compact bicomponent-permanent-magnet design presented in this study is capable of generating a high magnetic field in a small volume while limiting the stray field, making it suitable for retrofitting existing experiments in diverse environments and applications.
PHYSICAL REVIEW APPLIED
(2021)
Article
Materials Science, Ceramics
Apsar Pasha, A. F. Abd El-Rehim, Atif Mossad Ali, K. M. Srinivasamurthy, S. O. Manjunatha, Shifa Wang, Jagadeesha Angadi
Summary: The fast development of compact and wearable opto-electronics devices requires high-performance electromagnetic shielding materials that are lightweight and flexible to address the problem of electromagnetic pollution. The current demand for absorption predominant microwave shielding materials is high to prevent electromagnetic interference in modern electronic devices and the environment. In this report, a multifunctional composite thin film material is synthesized, which combines exceptional electromagnetic interference (EMI) shielding, mechanical flexibility, and magnetic properties for portable and wearable electronic devices operating at GHz frequencies. By doping samarium and cesium nanoparticles into Co0.5Ni0.5Fe2-x-yO4, the composite thin films exhibit superior conductivity and enhanced dielectric and magnetic properties. With improved dielectric and magnetic properties, the 0.4 mm thick x,y = 0.02 ferrites-based thin film nanocomposite demonstrates outstanding absorption-dominated electromagnetic shielding responses of -23 dB, equivalent to 99.67% shielding efficiency in broad band microwave frequencies. Furthermore, these material-based nanocomposite shields exhibit excellent stability in EMI shielding efficiency under different mechanical stretching strains. In addition, the nanocomposite thin film shows exceptional strain sensing behavior, highlighting its multifunctional applications. Due to its unique properties of light weight, flexibility, outstanding EMI shielding effectiveness, and excellent strain sensing behavior, these ferrites-based material thin films can be used in flexible and comfortable electronic devices, such as crafty jacket shields.
CERAMICS INTERNATIONAL
(2023)
Article
Engineering, Electrical & Electronic
Vasyl Chasnyk, Dmytro Chasnyk, Igor Fesenko, Oksana Kaidash, Volodymyr Turkevych
Summary: The dielectric characteristics of AlN-based composites with different contents of conducting particles were analyzed, showing that the real and imaginary parts of the dielectric constant reach maximum values when the content of conductive particles approaches the percolation threshold. These composites have low dielectric losses compared to polycrystalline AlN ceramics and show high absorption of microwave radiation, making them promising materials for microwave devices.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Materials Science, Multidisciplinary
Pham Thi Thanh, Nguyen Huy Ngoc, Kieu Xuan Hau, Nguyen Hai Yen, Truong Viet Anh, Nguyen Huy Dan
Summary: This work investigates the microstructure and magnetic properties of sintered Nd16.5Fe77B6.5 magnets with intergranular addition of Dy30Nd17Pr3Al40Cu10. The study shows that the coercivity of the added magnets increases significantly, while their remanence decreases with increasing Dy30Nd17Pr3Al40Cu10 fraction. By adding Dy30Nd17Pr3Al40Cu10 compound to grain boundary, the Dy concentration can be reduced by 60 wt.% compared to the conventional method.
MATERIALS TRANSACTIONS
(2023)
Article
Physics, Applied
Sagar E. Shirsath, R. H. Kadam, K. M. Batoo, Danyang Wang, Sean Li
Summary: In this study, the magnetic properties of Sr0.8Ca0.2AlxCoxFe12-2xO19 hexagonal ferrites were improved through Co2+-Al3+ substitution. These ferrites show great potential as rare earth-free magnets with improved saturation magnetization, coercivity, and microwave absorption characteristics. This research highlights the possibility of using hexagonal ferrites as alternatives to rare earth-based permanent magnets.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Chemistry, Physical
Magdy Khalil, Gehan Abdel Rahman Sadek Dakroury, Emad Hassan Borai
Summary: Due to the growing demand for rare-earth elements in high-tech applications, new sustainable approaches to rare earth element recycling and separation have been developed. In this study, a novel nano composite, SA-g-(PAA/CuO), was created for the sorption and separation of rare earth elements. The results showed that the composite efficiently separates different rare earth elements based on their properties.
SURFACES AND INTERFACES
(2022)
Article
Nanoscience & Nanotechnology
Qiong Wu, Xiangyu Ma, Ming Yue, Liying Cong, Zhenhui Ma, Dongtao Zhang, Yuqing Li, Yatao Wang
Summary: Specially designed SmCo5/Co magnetic nanocomposites were fabricated by a bottom-up process, showing high magnetic performance with bi-anisotropic properties.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Applied
Qi Jia, Xin Han, Yuxin Liu, Xianquan Liao, Jing Zhou
Summary: In this study, a H2S-responsive rare-earth nanocomposite was constructed for synergistic chemotherapy-photothermal therapy (CT-PTT). The nanocomposite loaded with a chemotherapeutic drug and a heat shock protein inhibitor achieved programmable CT-PTT therapy activated by a single H2S trigger. Through ratiometric imaging, precise treatment timing for photothermal therapy was achieved, and the treatment effect was enhanced with the help of the inhibitor. This work provides new ideas for designing tumor microenvironment-responsive therapeutic agents for programmable synergistic therapy.
JOURNAL OF RARE EARTHS
(2022)
Article
Physics, Applied
Minyeong Choi, Yang-Ki Hong, Hoyun Won, Gary J. Mankey, Chang-Dong Yeo, Woncheol Lee, Myung-Hwa Jung, Taegyu Lee, Jong-Kook Lee
Summary: The study demonstrates that rare-earth free ferromagnetic MnBi exhibits a positive temperature coefficient of coercivity, but undergoes a structural phase transformation at high temperatures. By controlling the positioning of copper occupancy, it is possible to effectively suppress Mn diffusion and raise the temperature of the phase transformation.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Chemistry, Physical
J. Zamora, T. Bautista, N. S. Portillo-Velez, A. Reyes-Montero, H. Pfeiffer, F. Sanchez-Ochoa, H. A. Lara-Garcia
Summary: Experimental and DFT studies were conducted on the structural, magnetic, and optical properties of RFeO3 perovskites. The perovskites exhibited an orthorhombic crystal structure and weak ferromagnetic behavior. They were confirmed to be semiconductors with a bandgap of approximately 2.1 eV.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xianxiang Lv, Jing Jin, Weiguang Yang
Summary: By depositing TiN and TiO2 surface layers on AlSi films, the electrochemical performance of silicon-based anodes can be significantly improved, suppressing volume expansion and promoting the formation of a stable SEI layer.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Sharafat Ali, Haider Ali, Syedul Hasnain Bakhtiar, Sajjad Ali, Muhammad Zahid, Ahmed Ismail, Pir Muhammad Ismail, Amir Zada, Imran Khan, Huahai Shen, Rizwan Ullah, Habib Khan, Mohamed Bououdina, Xiaoqiang Wu, Fazal Raziq, Liang Qiao
Summary: The construction and optimization of redox-heterojunctions using a bifunctional phosphate as an electron-bridge demonstrated significant improvements in photo catalytic activity, including enhanced dispersion, reduced interfacial migration resistance, and increased abundance of active-sites.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Ren-Ni Luan, Na Xu, Chao-Ran Li, Zhi-Jie Zhang, Yu-Sheng Zhang, Jun Nan, Shu-Tao Wang, Yong-Ming Chai, Bin Dong
Summary: Extensive research has revealed that oxygen evolution reaction (OER) in alkaline conditions involves dynamic surface restructuring. The development and design of sulfide/oxide pre-catalysts can reasonably adjust the composition and structure after surface reconstruction, which is crucial for OER. This study utilized a simple two-step hydrothermal method to achieve in situ S leaching and doping, inducing the composition change and structure reconstruction of CoFe oxides. The transformed FeOOH and CoOOH exhibited excellent OER activity and could be easily mass-produced using low-cost iron based materials and simple methods.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Jun'an Lai, Daofu Wu, Peng He, Kang An, Yijia Wang, Peng Feng, WeiWei Chen, Zixian Wang, Linfeng Guo, Xiaosheng Tang
Summary: Zero-dimensional organic-inorganic metal halides (OMHs) are gaining attention in the fabrication of light-emitting diodes due to their broad emission band and high photoluminescence quantum yield. This work synthesized a zero-dimensional organic tetraphenylphosphonium bismuth chloride (TBC) that showed efficient blue light emission, with the emission mechanism attributed to the transition of Bi3+ ions. White light-emitting diodes (WLEDs) were fabricated using TBC, along with green-emitting and red-emitting single crystals, achieving single-component white emissions. These findings demonstrate the different emission mechanism of ns2 ions-based OMHs and highlight the potential of bismuth-based OMHs in WLEDs applications.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xuewei Liang, Yunhai Su, Taisen Yang, Zhiyong Dai, Yingdi Wang, Xingping Yong
Summary: The revolutionary design concept of high-entropy alloys has brought new opportunities and challenges to the development of advanced metal materials. In this work, AlCrCuFe2NiTix high-entropy flux cored wires were prepared by combining the design idea of a high-entropy alloy with the characteristics of flux cored wire. AlCr-CuFe2NiTix high-entropy surfacing alloys were prepared using gas metal arc welding technology. The wear properties of the alloys were analyzed, and the phase composition, microstructure, strengthening mechanism, and wear mechanism were discussed. The results show that the alloys exhibit a dendritic microstructure with BCC/B2 + FCC phases. Increasing Ti content leads to the precipitation of Laves phase. The alloys show improved microhardness and wear resistance due to the precipitation of coherent B2 and Laves phases. However, excessive Ti addition results in the increase of Laves phase and reduced wear resistance of the alloys.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
M. Vadivel, M. Senthil Pandian, P. Ramasamy, Qiang Jing, Bo Liu
Summary: This work presents the enhanced photocatalytic and electrochemical performance of g-C3N4 assisted PAA on CoFe2O4 ternary nanocomposites. The incorporation of PAA and g-C3N4 improves the separation efficiency of photogenerated charge carriers, resulting in superior photocatalytic degradation and high specific capacitance values.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Vibhu T. Sivanandan, Ramany Revathy, Arun S. Prasad
Summary: In this study, pure and doped cobalt ferrite nanoparticles were prepared using the sol-gel auto-combustion method with the aid of lemon juice as eco-fuel. The crystal structure, lattice parameter, crystallite size, microstrain, optical parameters, and room temperature magnetic properties of the samples were analyzed. The effect of doping on the magnetic properties was also investigated.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Qing Guo, Bowen Zhang, Benzhe Sun, Yang Qi
Summary: This study prepared ZnO films with various nonpolar preferred orientations using conventional chemical bath deposition method and characterized their growth process and mechanism. It was found that the type and concentration of nitrate could control the preferred orientation and surface roughness of ZnO films. Additionally, ZnO films with different preferred orientations exhibited different optical properties.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Chong Zhang, Yan Liu, Zhaoyan Wang, Hang Yang
Summary: In this study, six bimetallic FeCo particles were synthesized via the hydrothermal method at different Fe:Co ratios. The Fe:Co ratio not only modulates the composition of the particles but also influences their structure and magnetic properties. The FeCo alloys showed a transformation from an Fe-based structure to a Co-based structure with increasing Co content. The Fe:Co ratio of 1:1 and 3:1 resulted in particles with the highest and lowest saturation magnetization, respectively.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Jianning Zhang, Jing Li, Yiren Wang, Xiaodong Mao, Yong Jiang
Summary: We conducted a study on the formation of ultra-fine Y-Ti-Ta-O nano-oxides in Ta+B micro-alloyed 13CrWTi-ODS alloys using electron microscopy and first-principles calculations. The Y-Ti-Ta-O nano-oxides were found to be mainly Y2(Ti,Ta)2O7, with an average size of 7 nm and a number density of 6.8 x 1023 m-3. Excess boron was found to enhance the adhesion of some low-sigma grain boundaries but weaken the Fe/Y2Ti2O7 interface, while excess tantalum enhanced the Fe/Y2Ti2O7 interface but caused serious degradation of grain boundaries.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Yirong Fang, Pei Cheng, Hang Yuan, Hao Zhao, Lishu Zhang
Summary: A new composite system of nitrogen-doped reduced graphene oxide and black phosphorus quantum dots has been developed for tumor therapy, showing improved electrochemical properties and stability. The system generates hydrogen peroxide and hydroxyl radical to effectively kill tumor cells.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xiufang Qin, Yuanli Ma, Hui Zhang, Ting Zhang, Fang Wang, Xiaohong Xu
Summary: The structure and magnetism of cobalt ferrites after Mn2+-Tb3+ co-doping were studied. Co-doped samples exhibited cubic spinel structure and spherical shape of ferrite nanoparticles. The redistribution of Co2+ and Fe3+ ions between octahedral and tetrahedral sites was observed due to Mn2+-Tb3+ co-doping. The coercivity and magnetization saturation of co-doped samples were significantly improved, leading to a maximum energy product that is 190% higher than that of the un-doped sample.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Ho Yeon Lee, Wonjong Yu, Yoon Ho Lee
Summary: Recently, there has been an increasing interest in developing ultra-fine nanostructured electrodes with extensive reaction areas to enhance the performance and low-temperature operation of solid oxide fuel cells. The use of a refined approach involving co-sputtering metal alloys and oxide targets has demonstrated the feasibility of nano-columnar structures in perovskite-based electrodes, expanding the temperature range of thin film electrodes. This study systematically examines the effects of chamber pressure control in the co-sputtering process and identifies the intricate relationship between sputtering pressure and film structure. By fine-tuning the columnar growth in the electrode, significant improvements in performance and thermo-mechanical properties were achieved, resulting in high-performance all-sputtered solid oxide fuel cells.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Qianyun Bai, Xiaoxiao Yan, Da Liu, Kang Xiang, Xin Tu, Yanhui Guo, Renbing Wu
Summary: This study proposes a simple method to develop a non-precious transition metal-based electrocatalyst with high catalytic activity and robustness for the hydrogen evolution reaction. The as-synthesized electrode exhibits a low overpotential and high current density, indicating its potential in energy conversion.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)