1
|
Dielectric properties and magnetic behavior OF Gd3+ substituted M-type SrFe12O19 nanoferrites by auto combustion method using urea and citric acid mixtures as a dual fuel. J SOLID STATE CHEM 2022. [DOI: 10.1016/j.jssc.2022.123465] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
2
|
Lakshmikantha J, Krishnamurthy G, Hanumantha Nayak R, Pari M, Ranjitha N, Naik N. Synthesis, Structure, Thermal, Magnetic, Dielectric Properties of Ce3+ Doped M-Type SrFe12O19 And Electrochemical Determination of L-Cysteine. INORG CHEM COMMUN 2022. [DOI: 10.1016/j.inoche.2022.110175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
3
|
Hu Z, Stenning GBG, Koval V, Wu J, Yang B, Leavesley A, Wylde R, Reece MJ, Jia C, Yan H. Terahertz Faraday Rotation of SrFe 12O 19 Hexaferrites Enhanced by Nb Doping. ACS APPLIED MATERIALS & INTERFACES 2022; 14:46738-46747. [PMID: 36194853 PMCID: PMC9585520 DOI: 10.1021/acsami.2c13088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 09/26/2022] [Indexed: 06/16/2023]
Abstract
The magneto-optical and dielectric behavior of M-type hexaferrites as permanent magnets in the THz band is essential for potential applications like microwave absorbers and antennas, while are rarely reported in recent years. In this work, single-phase SrFe12-xNbxO19 hexaferrite ceramics were prepared by the conventional solid-state sintering method. Temperature dependence of dielectric parameters was investigated here to determine the relationship between dielectric response and magnetic phase transition. The saturated magnetization increases by nearly 12%, while the coercive field decreases by 30% in the x = 0.03 composition compared to that of the x = 0.00 sample. Besides, the Nb substitution improves the magneto-optical behavior in the THz band by comparing the Faraday rotation parameter from 0.75 (x = 0.00) to 1.30 (x = 0.03). The changes in the magnetic properties are explained by a composition-driven increase of the net magnetic moment and enhanced ferromagnetic exchange coupling. The substitution of the donor dopant Nb on the Fe site is a feasible way to obtain multifunctional M-type hexaferrites as preferred candidates for permanent magnets, sensors, and other electronic devices.
Collapse
Affiliation(s)
- Zimeng Hu
- School
of Engineering and Materials Science, Queen
Mary University of London, Mile End Road, LondonE1 4NS, United Kingdom
| | - Gavin B. G. Stenning
- ISIS
Neutron and Muon Source, Rutherford Appleton
Laboratory, Didcot, OxfordshireOX11 0QX, United Kingdom
| | - Vladimir Koval
- Institute
of Materials Research, Slovak Academy of
Sciences, Kosice04001, Slovakia
| | - Jiyue Wu
- School
of Engineering and Materials Science, Queen
Mary University of London, Mile End Road, LondonE1 4NS, United Kingdom
| | - Bin Yang
- Faculty
of Science and Engineering, University of
Chester, Parkgate Road, ChesterCH1 4BJ, United Kingdom
| | - Alisa Leavesley
- Virginia
Diodes Inc., 979 2nd
St SE #309, Charlottesville, Virginia22902, United
States
- Thomas Keating
Ltd, Billingshurst, West SussexRH14 9SH, United Kingdom
| | - Richard Wylde
- Thomas Keating
Ltd, Billingshurst, West SussexRH14 9SH, United Kingdom
| | - Michael John Reece
- School
of Engineering and Materials Science, Queen
Mary University of London, Mile End Road, LondonE1 4NS, United Kingdom
| | - Chenglong Jia
- Key
Laboratory for Magnetism and Magnetic Materials of MOE, Lanzhou University, Lanzhou730000, P. R. China
| | - Haixue Yan
- School
of Engineering and Materials Science, Queen
Mary University of London, Mile End Road, LondonE1 4NS, United Kingdom
| |
Collapse
|
4
|
Musa IM, Abdu Y, Mohammed J, Srivastava AK. Structural, Dielectric and Raman Spectroscopy of La
3+
–Ni
2+
–Zn
2+
Substituted M‐Type Strontium Hexaferrites. CRYSTAL RESEARCH AND TECHNOLOGY 2021. [DOI: 10.1002/crat.202100005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ibrahim Murtala Musa
- Department of Physics Faculty of Science Federal University Dutse P.M.B. 7156 Dutse Jigawa Nigeria
| | - Yunusa Abdu
- Department of Physics Bayero University Kano P. M. B. 3011 Kano Kano Nigeria
| | - Jibrin Mohammed
- Department of Physics Faculty of Science Federal University Dutse P.M.B. 7156 Dutse Jigawa Nigeria
| | - Ajeet Kumar Srivastava
- Department of Physics School of Physical Sciences and Chemical Engineering Lovely Professional University Phagwara Punjab 144411 India
| |
Collapse
|
5
|
Liu H, Wang J, Zhang G, Han Y, Wu B, Gao C. Pressure effects on the metallization and dielectric properties of GaP. Phys Chem Chem Phys 2021; 23:26829-26836. [PMID: 34817490 DOI: 10.1039/d1cp03889c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In situ impedance measurement, resistivity measurements and first-principles calculations have been performed to investigate the effect of high pressure (up to 30.2 GPa) on the metallization and dielectric properties of GaP. It is found that the carrier transport process changes from mixed grain and grain boundary conduction to pure grain conduction at 5.8 GPa, and due to pressure-induced structural phase transition, the resistance drops drastically by three orders of magnitude at 25.5 GPa. Temperature dependence of resistivity measurements and band structure calculations suggest the occurrence of a semiconductor-metal transition. Combining differential charge density and dielectric analysis, it is observed that the electron localization is weakened, which leads to increased polarization and larger relative permittivity in the zb structure. After the phase transition, both the polarization and the relative permittivity decrease. Pressure increases the complex dielectric constant and dielectric loss factor, due to the increase in relaxation polarization and the scattering effect of carriers. Moreover, by comparing the high-pressure behavior of GaP, GaAs and GaSb, the changes in the electronic structure and electric transport process caused by the phase transition can be understood, which can enable us to better understand the metallization behavior and dielectric properties of Ga-based III-V family semiconductors under pressure, and stimulate the design and modification of other related group III-V semiconductors for optoelectronic devices and sensors.
Collapse
Affiliation(s)
- Hao Liu
- State Key Laboratory for Superhard Materials, Jilin University, Changchun 130012, China. .,Department of Physics, College of Science, Yanbian University, Yanji, Jilin 133002, China.
| | - Jia Wang
- State Key Laboratory for Superhard Materials, Jilin University, Changchun 130012, China. .,Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun 130052, China
| | - Guozhao Zhang
- State Key Laboratory for Superhard Materials, Jilin University, Changchun 130012, China. .,Shandong Key Laboratory of Optical Communication Science and Technology, School of Physical Science and Information Technology, Liaocheng University, Liaocheng 252059, China
| | - Yonghao Han
- State Key Laboratory for Superhard Materials, Jilin University, Changchun 130012, China.
| | - Baojia Wu
- Department of Physics, College of Science, Yanbian University, Yanji, Jilin 133002, China.
| | - Chunxiao Gao
- State Key Laboratory for Superhard Materials, Jilin University, Changchun 130012, China.
| |
Collapse
|
6
|
Anisotropic characteristics and improved magnetic performance of Ca-La-Co-substituted strontium hexaferrite nanomagnets. Sci Rep 2020; 10:15929. [PMID: 32985510 PMCID: PMC7522080 DOI: 10.1038/s41598-020-72608-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 09/02/2020] [Indexed: 11/17/2022] Open
Abstract
Recent studies on next-generation permanent magnets have focused on filling in the gap between rare-earth magnets and rare-earth-free magnets, taking into account both the cost-effectiveness and magnetic performance of the magnetic materials. As an improved rare-earth-free magnet candidate, here, Ca-substituted M-type Sr-lean hexaferrite particles within a nano- to micro-scale regime, produced using an ultrasonic spray pyrolysis method, are investigated. Theoretically, the maximum coercivity (Hc) can be achieved in submicron Sr-ferrite crystals (i.e., 0.89 μm). The plate-like resultants showed a significant enhancement in Hc, up to a record high of 7880.4 Oe, with no deterioration in magnetization (M: 71–72 emu/g). This resulted in more favorable magnetic properties than those of the traditional Sr–La–Co ferrites. On the basis of microstructural analysis and fitting results based on the law of approach to saturation method, the Ca-substitution effects on the change in size and anisotropic characteristics of the ferrite particles, including pronounced lateral crystal growth and a strong increase in magnetocrystalline anisotropy, are clearly demonstrated. The cost-effective, submicron, and Ca-substituted Sr-ferrite is an excellent potential magnet and moreover may overcome the limitations of traditional hard magnetic materials.
Collapse
|
7
|
Developing the magnetic, dielectric and anticandidal characteristics of SrFe12O19/(Mg0.5Cd0.5Dy0.03Fe1.97O4)x hard/soft ferrite nanocomposites. J Taiwan Inst Chem Eng 2020. [DOI: 10.1016/j.jtice.2020.07.022] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|