Article
Chemistry, Physical
Yongsheng Liu, Jiaying Jin, Xinhua Wang, Mi Yan
Summary: Through the methods of grain boundary restructuring and grain boundary diffusion process, the introduction of (Pr, Nd)H-x into La-Ce-40 sintered magnet successfully increased the coercivity of the magnet. The grain boundary diffusion process can maintain a higher remanence compared to grain boundary restructuring.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Zhi Jia, Mingpeng Kou, Shuai Cao, Xintong Yang, Guangfei Ding, Shuai Guo, Xiaodong Fan, Bo Zheng, Renjie Chen, Aru Yan
Summary: The magnetic properties and microstructure of Nd-Ce-Y-Fe-B magnets with Nd-Co boundary additions were systematically investigated. It was found that appropriate Nd-Co addition could simultaneously improve the coercivity, remanence, and Curie temperature of the magnets. The coercivity enhancement was attributed to widened grain boundary width and reduced magnetic exchange coupling, while the remanence improvement was achieved through partial substitution. This study provides new insights into the preparation of high-abundance magnets.
RESULTS IN PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Yu-Cai Wu, Xi -Chun Zhong, Yuan-Xin Li, Xuan Huang, Jiao-Hong Huang, Cui-Lan Liu, Zhong-Wu Liu, Wan-Qi Qiu, Ming -Long Zhong, Zhen-Chen Zhong, R. V. Ramanujan
Summary: LaFe11.8Si1.2/16wt%La65Co35 samples were prepared by spark plasma sintering (SPS) and subsequent annealing. The La65Co35 binder increased the 1:13 phase content, and the alpha-Fe phase formed and disappeared during annealing. The sample annealed for 0.5 h showed a distinct core-shell structure, desirable table-like (-Delta S-M) -T curve, and higher RC value. The diffusion of Co was hindered by the growth of La5Si3 phase. Samples annealed for 24 h achieved larger (-Delta S-M)(max) and (sigma(bc))(max) values. The method combining SPS and diffusion annealing is promising for preparing La-Fe-Si based magnetocaloric composites with good properties.
MATERIALS RESEARCH BULLETIN
(2023)
Article
Materials Science, Multidisciplinary
Jia Li, Shihui Li, Qingrong Yao, Weichao Huang, Jianqiu Deng, Jiang Wang, Guanghui Rao, Huaiying Zhou
Summary: The addition of Tb6Fe13Cu was found to significantly improve the intrinsic coercivity and corrosion resistance of Nd-Fe-B magnets, leading to the formation of a Tb-rich shell structure, optimization in distribution/morphology of intergranular phases, and stabilization of RE-rich phases.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Chemistry, Physical
Fugang Chen, Tieqiao Zhang, Yong Zhao, Xiaoli Wang, Caiping Jiang, Jinlu Chen, Wenqiang Zhao
Summary: The demagnetization field distribution of magnetized Nd-Fe-B magnet was quantitatively calculated and analyzed. Multilayered composite Nd-Fe-B magnets were designed and fabricated with specific coercivity gradient distributions lower than the demagnetization field gradient. It was found that the low coercivity interlayer magnets did not significantly decrease the overall magnetic properties, and effective self-bonding was observed between adjacent Nd-Fe-B magnets.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Applied
Haibo Xu, Qingmei Lu, Liying Cong, Haowen Tian, Weiqiang Liu, Youhao Liu, Yunqiao Wang, Jingwu Chen, Xiaofei Yi, Ming Yue
Summary: The structural and magnetic properties of recycled Nd-Fe-B powders prepared using calcium hydride (CaH2) particles as the reducing agent were investigated. The use of CaH2 resulted in finer particle size, better size distribution, and lower impurity content compared to traditional calcium granules. Additionally, the CaH2-reduced powders exhibited higher room-temperature magnetization.
JOURNAL OF RARE EARTHS
(2022)
Article
Materials Science, Multidisciplinary
Yuye Wu, Konstantin P. Skokov, Lukas Schafer, Fernando Maccari, Alex Aubert, Ziyuan Rao, Kevin Schweinar, Baptiste Gault, Hao Xu, Chengbao Jiang, Oliver Gutfleisch
Summary: In this study, the similarities and differences between Nd-Fe-B and Nd-Co-B magnets were investigated. It was found that the microstructure and origin of the high coercive state in Nd-Co-B magnets, unlike Nd-Fe-B magnets, have been less studied. Nd-Co-B magnets consist of multiple exchange-coupled ferromagnetic phases.
Article
Materials Science, Multidisciplinary
Shuo Gao, Xiangke Lv, Xiaoqian Bao, Rongxia Wang, Shanshun Zha, Jiheng Li, Xuexu Gao
Summary: Commercial Nd-Fe-B sintered magnets were processed with Pr-Cu, Pr-Al, and Pr-Tb-Cu alloys through grain boundary diffusion, resulting in increased coercivity but reduced bending strength. Microstructure analysis showed that Cu enriched at grain boundaries, while Tb and Al atoms diffused into the main phase and caused lattice distortion, leading to decreased bending strength.
Article
Materials Science, Multidisciplinary
Zhi Li, Yu-Qing Li, Wei-Qiang Liu, Dan Wu, Hao Chen, Wei-Xing Xia, Ming Yue
Summary: The reduction in coercivity of high La-Ce-containing Nd-Fe-B sintered magnets is mainly due to the poor magnetic isolation of grain boundaries and a higher proportion of reversible portions in magnets with a large content of La-Ce, leading to decreased performance.
Article
Chemistry, Applied
Xiaolian Liu, Mengjie Pan, Pei Zhang, Tianyu Ma, Lizhong Zhao, Lingwei Li
Summary: Homogeneous substitution of Dy for Nd in the 2:14:1 phase can enhance coercivity but reduce remanence. A comparative study showed that multi-main-phase magnet with inhomogeneous Dy distribution has better magnetic properties and thermal stability than single-main-phase magnet with homogeneous Dy distribution. The multi-main-phase magnet exhibited higher coercivity, remanence, and energy product at room temperature and over a wide temperature range.
JOURNAL OF RARE EARTHS
(2021)
Article
Chemistry, Multidisciplinary
Hong-Zhi Wang, Zhi-Jie Li, Zheng Liu, Yan Yan, Peng-Yuan Zhi
Summary: By adding Ho nanopowder to the grain boundaries of Nd-Fe-B magnetic materials, the magnetic, mechanical properties, and corrosion-resistant performance were improved. The optimum combination of properties was achieved when adding 0.6% Ho, with enhanced magnetic properties and improved corrosion resistance.
JOURNAL OF NANOPARTICLE RESEARCH
(2021)
Article
Materials Science, Multidisciplinary
Qingzheng Jiang, Guo Yang, Chuanjia Zhao, Qingfang Huang, Weiguo Wei, Huixia Li, Qiang Ma, Zhenchen Zhong
Summary: By using grain boundary diffusion method with PrCuGa as the diffusion source, the magnetic properties of commercial Nd-La-Y-Fe-B magnets were successfully improved. After annealing treatment, the Hcj and (BH)max of the magnets increased significantly. This improvement is mainly attributed to the partial replacement of La by Pr, forming (Pr,Nd,La, Y)2Fe14B with higher intrinsic properties.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2023)
Article
Chemistry, Applied
Jia Li, Qingrong Yao, Weichao Huang, Jue Xie, Zhilin Mo, Jianqiu Deng, Jiang Wang, Guanghui Rao, Huaiying Zhou
Summary: The addition of low-melting-point eutectic Tb68Ni32 alloy powders can enhance the coercivity and slightly affect the remanence of Nd-Fe-B sintered magnets, while also improving their corrosion resistance.
JOURNAL OF RARE EARTHS
(2022)
Article
Materials Science, Multidisciplinary
Yu-Cai Wu, Yuan-Xin Li, Xi -Chun Zhong, Cui-Lan Liu, Jiao-Hong Huang, Hong-Ya Yu, Zhong-Wu Liu, Ming -Long Zhong, Zhen-Chen Zhong, Raju V. Ramanujan
Summary: LaFeSi bulk magnetocaloric materials were prepared using hot-pressing sintering and spark plasma sintering techniques. The reduction of porosity was found to enhance the magnetocaloric effect.
MATERIALS RESEARCH BULLETIN
(2022)
Article
Materials Science, Multidisciplinary
Shu Wang, Hong-Wei Wang, Bo-Ren Hou, Tian-Yu Liu, Li-Zhu Wang, Ji-Bing Sun
Summary: The addition of Al-Cu-Fe alloy changes the crystallization process and microstructure of Nd-Fe-Co-B ribbons, with different effects observed at different addition levels. 1 wt% addition can enhance magnetic properties, while excessive additions deteriorate the magnetic properties.
MATERIALS CHEMISTRY AND 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)