通过单原子Co/TiO2纳米结构中的氧空缺控制来优化铁磁稳定性
Vinod K Paidi1, Byoung-Hoon Lee2,3, Alex Taekyung Lee4
1Experiments Division, European Synchrotron Radiation Facility, Grenoble 38043, Cedex 9, France.
概括
氧气空隙显著提高了配二氧化物纳米颗粒中的室温铁磁性. 这一发现对于设计先进的稀释磁性半导体至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 氧气空缺对于理解材料中的纳米磁性和电子结构至关重要.
- 稀释磁性半导体需要精确控制磁性和电子状态.
研究的目的:
- 为了研究氧气空缺在单原子嵌入的二氧化 (TiO2) 纳米粒子的室温铁磁性中的作用.
- 阐明电子结构,氧气空位和磁性特性之间的相关性.
主要方法:
- 通过热力学再分配合成单分散的TiO2纳米粒子,并加入单个原子.
- 基于同步的先进X射线技术用于结构和电子分析.
- 密度函数理论 (DFT) 计算以建模磁相互作用和电子结构.
主要成果:
- 证实缺少三价,表明它不会影响铁磁稳定性.
- 观察到CO2+离子之间的固有铁磁稳定性较弱.
- 来自氧气空缺的电子兴奋剂显著增强了铁磁稳定性,解释了观察到的室温铁磁.
- 对于氧空位复合体 (CoTi + VO) 发现了增强的铁磁相互作用.
结论:
- 氧气空缺是单原子添加TiO2纳米结构中室温铁磁性的主要机制.
- 这些发现为设计和优化单原子合纳米材料的磁性特性提供了一条途径.
- 该研究强调了热力学再分配和先进的特征化技术在纳米结构中探索磁性的潜力.
更多相关视频
10:57Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
18.1K
10:45Stable Aqueous Suspensions of Manganese Ferrite Clusters with Tunable Nanoscale Dimension and Composition
Published on: February 5, 2022
4.2K
相关概念视频
Ferromagnetism
2.4K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
2.4K
Valence Bond Theory
8.5K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
8.5K
Diamagnetism
2.4K
Materials consisting of paired electrons have zero net magnetic moments. However, when these materials are placed under an external magnetic field, the moments opposite to the field are induced. Such materials are called diamagnets. Diamagnetism is the response of the diamagnets when placed in an external magnetic field.
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....
2.4K
Properties of Transition Metals
25.1K
Transition metals are defined as those elements that have partially filled d orbitals. As shown in Figure 1, the d-block elements in groups 3–12 are transition elements. The f-block elements, also called inner transition metals (the lanthanides and actinides), also meet this criterion because the d orbital is partially occupied before the f orbitals.
25.1K
