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With fast-growing demands in electrical propulsion, power and energy resilience technologies, search for cheaper and widely available permanent magnets with high saturation magnetization, high uniaxial magnetocrystalline anisotropy, and high Curie temperature becomes ever so important. This undertaking is even more urgent for subsea power conversion, naval energy resilience, and electrical systems that support naval warfighting technologies. Today’s search focuses exclusively on reducing the content of the expensive rare-earth and heavy metals in highperformance, thermally stable permanent magnets. Project Objectives: The ultimate goal of this proposal is to search for novel, inexpensive nanomagnetic materials through a high throughput computational investigations supplemented by materials fabrication and characterization experiments. The objective is obtaining of compositional and structural design information for rare-earth free/reduced high performance permanent magnets. Project Deliverables: This project will provide extensive information on compositional and structural landscape of new thermally stable, high-performance permanent magnets with high saturation magnetization and uniaxial magnetocrystalline anisotropy, thus large energy product, and high Curie temperature, that are based on transition metals with none or reduced rare-earth content. Project Scientific Impact: This effort will reduce existing knowledge gaps in atomistic under-standing of rareearth free/reduced permanent magnets and improve physical insights into the mechanisms of high-performance, lowcost permanent magnetic materials. Project Wider Impact: This project will fund 4 PhD-level graduate students and 3 postdoctoral fellow researchers at full time. At least two graduate students will graduate completing their thesis on the research conducted during this project. In addition, one full-time contractor will be employed to maintain computational and experimental facilities, and one full-time project manager for logistics and administrative hurdles, annual project review meetings, and outreach activities. Project Concept: We aim to pursue a novel strategy, in which the intrinsic and extrinsic hard magnetic properties of iron-based Sm–Fe–M–N (M = 3d and 3p metals; N = B, C, N, and O), Fe–Ni–M–N, and Fe–Co–M–N compounds at elevated temperatures will be investigated computationally, while systematically sampling their compositional and structural variances. This effort will use quantum computational research tools based on the Density Functional Theory to calculate lattice, thermodynamic energetics, electronic and magnetic structures. Monte Carlo simulation methods will be employed to calculate finite temperature properties Curie temperature, hysteresis loop curve, and maximum energy density product. Insights gained from the computational calculations will then inform the fabrication and characterization of the candidate alloys. Fabrications will employ induction melting and chemical synthesis methods, while characterizations will use X-ray diffraction, X-ray fluorescence, field emission scanning electron microscope, and scanning transmission electron microscopy. Temperature dependent magnetic properties will be measured using the superconducting quantum interference device magnetometer.
With fast-growing demands in electrical propulsion, power and energy resilience technologies, search for cheaper and widely available permanent magnets with high saturation magnetization, high uniaxial magnetocrystalline anisotropy, and high Curie temperature becomes ever so important. This undertaking is even more urgent for subsea power conversion, naval energy resilience, and electrical systems that support naval warfighting technologies. Today’s search focuses exclusively on reducing the content of the expensive rare-earth and heavy metals in highperformance, thermally stable permanent magnets. Project Objectives: The ultimate goal of this proposal is to search for novel, inexpensive nanomagnetic materials through a high throughput computational investigations supplemented by materials fabrication and characterization experiments. The objective is obtaining of compositional and structural design information for rare-earth free/reduced high performance permanent magnets. Project Deliverables: This project will provide extensive information on compositional and structural landscape of new thermally stable, high-performance permanent magnets with high saturation magnetization and uniaxial magnetocrystalline anisotropy, thus large energy product, and high Curie temperature, that are based on transition metals with none or reduced rare-earth content. Project Scientific Impact: This effort will reduce existing knowledge gaps in atomistic under-standing of rareearth free/reduced permanent magnets and improve physical insights into the mechanisms of high-performance, lowcost permanent magnetic materials. Project Wider Impact: This project will fund 4 PhD-level graduate students and 3 postdoctoral fellow researchers at full time. At least two graduate students will graduate completing their thesis on the research conducted during this project. In addition, one full-time contractor will be employed to maintain computational and experimental facilities, and one full-time project manager for logistics and administrative hurdles, annual project review meetings, and outreach activities. Project Concept: We aim to pursue a novel strategy, in which the intrinsic and extrinsic hard magnetic properties of iron-based Sm–Fe–M–N (M = 3d and 3p metals; N = B, C, N, and O), Fe–Ni–M–N, and Fe–Co–M–N compounds at elevated temperatures will be investigated computationally, while systematically sampling their compositional and structural variances. This effort will use quantum computational research tools based on the Density Functional Theory to calculate lattice, thermodynamic energetics, electronic and magnetic structures. Monte Carlo simulation methods will be employed to calculate finite temperature properties Curie temperature, hysteresis loop curve, and maximum energy density product. Insights gained from the computational calculations will then inform the fabrication and characterization of the candidate alloys. Fabrications will employ induction melting and chemical synthesis methods, while characterizations will use X-ray diffraction, X-ray fluorescence, field emission scanning electron microscope, and scanning transmission electron microscopy. Temperature dependent magnetic properties will be measured using the superconducting quantum interference device magnetometer.
Түлхүүр үгс:Our research project will be focused on the study to find candidate materials with the applications of spintronics and topological insulators within the advanced energy related magnetic materials, and their magnetic property, magnetic anisotropy and magnetostriction. The project consists of three parts and we will be published one article as first and corresponding author or two articles as co - author.
Our research project will be focused on the study to find candidate materials with the applications of spintronics and topological insulators within the advanced energy related magnetic materials, and their magnetic property, magnetic anisotropy and magnetostriction. The project consists of three parts and we will be published one article as first and corresponding author or two articles as co - author.
Түлхүүр үгс:Today’s demand for electric vehicle and energy storage applications requires breakthroughs that lead to a drastic increase in the storage capacity of the anodes and cathodes in lithium ion batteries (LIBs), and improvements in charging rate and lifetime are also called for. The current LIB anode and cathode materials are typically based on graphite and lithium cobalt oxide (LiCoO2). The anode has a fundamental Li ion storage limit of LiC6, which corresponds to a specific capacity of 372 mAh/g. To realize a full-scale commercial electric vehicle, the anode and cathode capacities should be boosted beyond the current limit. To this end, a variety of candidate materials, including silicon, germanium, and tin, and various metal alloys for anode, and lithium phosphide (LiFePO4) and lithium fluorosulphate (LiFeSO4F) for cathode have been evaluated when comprised in composites as high-capacity active materials. Although there have been numerous reports on the improvement of storage capacities of these anode and cathode materials, the renewal of research targets seemingly resides in the use of (1) two-dimensional materials such as schwarzite-type carbon and possibly transition metal dichalcogenides as anode materials (e.g., MoS2), and (2) new compounds of LiFePO4- and LiFeSO4F-type structures. Indeed, we have previously published a few peer-review articles on the LIB anode (Nature Scientific Reports 3, 1917 (2013), J. Am. Chem. Soc. 135, 8720 (2013), Carbon 66, 39 (2014), and Angew. Chem. Int. Ed. 53, 13064 (2014)) and cathode materials (J. Appl. Phys. 113, 17B302 (2013)). However, we and other groups have not yet explored the possibility of using schwarzite-type carbon and MoS2 for the LIB anode and new compounds of LiFePO4- and LiFeSO4F-type materials for the LIB cathode applications. Based on our research experience on LIB, we now expect to study these materials during the present grant period. On the other hand, single-molecule magnets (usually transition metals, e.g., cobalt) have great potential for quantum spin processing or spin-dependent electronics because of their small size and intrinsic magnetism. In particular, they are expected to have up to 1000 times more energy-efficient and data storage density than current technologies in nonvolatile memory devices such as magnetic random access memory (MRAM). However, single-molecule magnets should be realized by properly selecting the contact medium. The contact medium plays an important role in determining the perpendicular magnetic anisotropy, which is the main decisive property of designing materials for the MRAM. The aforementioned two-dimensional materials (schwarzite-type carbon and MoS2) would be used for the contact medium that can adsorb single-molecule magnets. Our (visiting scholar and host professor) research experience in this information storage research field is indeed sufficient, and we in collaboration with the leading experts in the USA, Japan, and Korea have published several articles in the renowned journals in the community (Physical Review B, Applied Physics Letters, Journal of Applied Physics, Journal of Nanoscience and Nanotechnology, Materials Letters, etc (as listed in Section 4)). We thus expect that the present grant would provide opportunities to explore the schwarzite-type carbon and MoS2 in corporate with single-molecule magnets, and release the achieved results during the grant period in the renowned high-impact journals.
Today’s demand for electric vehicle and energy storage applications requires breakthroughs that lead to a drastic increase in the storage capacity of the anodes and cathodes in lithium ion batteries (LIBs), and improvements in charging rate and lifetime are also called for. The current LIB anode and cathode materials are typically based on graphite and lithium cobalt oxide (LiCoO2). The anode has a fundamental Li ion storage limit of LiC6, which corresponds to a specific capacity of 372 mAh/g. To realize a full-scale commercial electric vehicle, the anode and cathode capacities should be boosted beyond the current limit. To this end, a variety of candidate materials, including silicon, germanium, and tin, and various metal alloys for anode, and lithium phosphide (LiFePO4) and lithium fluorosulphate (LiFeSO4F) for cathode have been evaluated when comprised in composites as high-capacity active materials. Although there have been numerous reports on the improvement of storage capacities of these anode and cathode materials, the renewal of research targets seemingly resides in the use of (1) two-dimensional materials such as schwarzite-type carbon and possibly transition metal dichalcogenides as anode materials (e.g., MoS2), and (2) new compounds of LiFePO4- and LiFeSO4F-type structures. Indeed, we have previously published a few peer-review articles on the LIB anode (Nature Scientific Reports 3, 1917 (2013), J. Am. Chem. Soc. 135, 8720 (2013), Carbon 66, 39 (2014), and Angew. Chem. Int. Ed. 53, 13064 (2014)) and cathode materials (J. Appl. Phys. 113, 17B302 (2013)). However, we and other groups have not yet explored the possibility of using schwarzite-type carbon and MoS2 for the LIB anode and new compounds of LiFePO4- and LiFeSO4F-type materials for the LIB cathode applications. Based on our research experience on LIB, we now expect to study these materials during the present grant period. On the other hand, single-molecule magnets (usually transition metals, e.g., cobalt) have great potential for quantum spin processing or spin-dependent electronics because of their small size and intrinsic magnetism. In particular, they are expected to have up to 1000 times more energy-efficient and data storage density than current technologies in nonvolatile memory devices such as magnetic random access memory (MRAM). However, single-molecule magnets should be realized by properly selecting the contact medium. The contact medium plays an important role in determining the perpendicular magnetic anisotropy, which is the main decisive property of designing materials for the MRAM. The aforementioned two-dimensional materials (schwarzite-type carbon and MoS2) would be used for the contact medium that can adsorb single-molecule magnets. Our (visiting scholar and host professor) research experience in this information storage research field is indeed sufficient, and we in collaboration with the leading experts in the USA, Japan, and Korea have published several articles in the renowned journals in the community (Physical Review B, Applied Physics Letters, Journal of Applied Physics, Journal of Nanoscience and Nanotechnology, Materials Letters, etc (as listed in Section 4)). We thus expect that the present grant would provide opportunities to explore the schwarzite-type carbon and MoS2 in corporate with single-molecule magnets, and release the achieved results during the grant period in the renowned high-impact journals.
Түлхүүр үгс:
