纳米 Zn(Ag,Ni) O 系统的光谱分析和在低温下观察超对磁性
Kamakhya Prakash Misra1, Saikat Chattopadhyay1, Atul Bandyopadhyay2
1Department of Physics, School of Basic Sciences, Manipal University Jaipur Jaipur Rajasthan 303007 India saikat.chattopadhyay@jaipur.manipal.edu the_saikat@yahoo.com.
Nanoscale advances
|July 25, 2024
概括
氧化 (ZnO) 与银 (Ag) 和 (Ni) 纳米颗粒的二元兴奋剂影响材料特性. 增加的Ni含量形成一个NiO阶段,影响磁性和光学特性,并观察到弱铁磁性.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 固态物理 固态物理
背景情况:
- 了解半导体纳米材料中共兴奋剂的影响对于开发先进的功能材料至关重要.
- 氧化 (ZnO) 是一种通用的半导体,在电子和自旋电子学中具有应用.
- 使用Ag和Ni进行二元兴奋剂的调查为修改ZnO的结构,光学和磁性特性提供了洞察力.
研究的目的:
- 通过sol-gel方法合成和表征纳米化氧化物,添加银和 (Zn(Ag,Ni) O).
- 研究不同 (Ni) 度对 ZnO 的结构,光学和磁性特性的影响.
- 了解二元兴奋剂时的相位演变和粒子形态变化.
主要方法:
- 对于Zn,Ag,Ni) O纳米颗粒的Sol-gel合成.
- 用X射线衍射 (XRD) 进行结构分析和晶格常数的确定.
- X射线光电子光谱 (XPS) 用于元素分析和兴奋剂分配.
- 场辐射扫描电子显微镜 (FESEM) 用于形态表征.
- 非线性光学测量和磁性分析 (磁化与温度对比).
主要成果:
- 超过3%的合导致形成一个独特的NiO阶段.
- ZnO的晶格常数基本上没有受到影响,而NiO的晶格常数随着Ni含量增加而下降.
- 随着NiO和Ag含量的增加,第二和第三波强度下降.
- 在FESEM中,发现了棕树形状的相互连接的粒子和链条,在较高度的Ni下,它们的形状转变为平板盘.
- 所有样本在低温 (≤50K) 时都表现出弱铁磁性,具有超偏磁性行为,归因于纳米尺寸效应和表面旋转.
结论:
- 用Ag和Ni对ZnO进行二进制兴奋剂会产生新的物质相,并改变粒子形态.
- 磁性属性主要由NiO相控制,ZnO宿主中Ni和Ag替代的贡献最小.
- 观察到的弱铁磁性与有限的纳米尺寸效应和合成纳米粒子中的表面现象有关.
相关概念视频
03:02Colors and Magnetism
11.6K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
11.6K
01:24Superconductor
1.1K
A substance that reaches superconductivity, a state in which magnetic fields cannot penetrate, and there is no electrical resistance, is referred to as a superconductor. In 1911, Heike Kamerlingh Onnes of Leiden University, a Dutch physicist, observed a relation between the temperature and the resistance of the element mercury. The mercury sample was then cooled in liquid helium to study the linear dependence of resistance on temperature. It was observed that, as the temperature decreased, the...
1.1K