吸收带可调节的La-Sr联合合的BaCo-W型六化物
Juan Li1,2, Xuetao Sun1,2
1College of Materials Science and Engineering, Zhejiang University of Technology, Hangzhou 310014, China.
Materials (Basel, Switzerland)
|September 9, 2023
概括
与La-Sr联合合的六表现出可调节的微波吸收特性. 优化的兴奋剂增强了电磁波散射,使它们成为雷达吸收应用的前景.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 电磁学 电磁学 电磁学 电磁学
背景情况:
- 六铁是先进的磁性材料,在微波吸收中具有潜在的应用.
- 调整六铁的组成对于优化它们的电磁性质至关重要.
研究的目的:
- 为了研究拉-Sr辅助兴奋剂对BaCo2Fe16O27六铁的结构和电磁性质的影响.
- 为了评估这些联合剂材料的微波吸收性能.
主要方法:
- 使用固态合成方法制备了Ba1-x(La0.5Sr0.5) xCo2Fe16O27六铁.
- 振动样品磁力计 (VSM) 用于分析磁性属性.
- 矢量网络分析仪 (VNA) 用于测量磁电性质并计算1-18 GHz的反射损失.
主要成果:
- 在x < 0.4时观察到W型六化物结构,在较高的兴奋剂水平时出现M型和螺旋相.
- 在x = 0.4.4时,达到76.2emu/g的最大和磁化 (Ms) 和60 Oe的最小强制性 (Hc).
- 优化的La-Sr兴奋剂引入了多孔性和增加了颗粒大小,增强了电磁波散射和将共振频率转移到较低的频段 (C,X,Ku).
- 在1.5毫米厚度 (X带) 时,x = 0.2的最小反射损失为-40.61dB,在2.5毫米 (C带) 时为-37.45dB,在x = 0.4.
- 在厚度小于2毫米的X和Ku带中观察到x = 0.6的良好吸收.
结论:
- 拉-Sr联合兴奋剂有效调整了CO2W铁的微波吸收特性.
- 准备好的材料具有出色的电磁波吸收能力,特别是在C,X和Ku频段.
- 由于其简单的制备和卓越的性能,这些La-Sr联合合的Co2W铁是先进的微波吸收应用的有希望的候选人.
相关概念视频
03:02Colors and Magnetism
11.8K
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...
11.8K
01:21IR Absorption Frequency: Hybridization
711
Hydrocarbons such as alkanes, alkenes, and alkynes show characteristic C–H stretching absorption bands. These IR stretching frequencies depend on the hybridization of the involved carbon atom and can be explained in terms of the s character of each hybridized atomic orbital.
Among the sp, sp2, and sp3 hybridized orbitals, sp orbitals have the maximum s character (50%). Consequently, the electrons are held more closely to the nucleus, resulting in stronger and shorter C–H bonds that...
Among the sp, sp2, and sp3 hybridized orbitals, sp orbitals have the maximum s character (50%). Consequently, the electrons are held more closely to the nucleus, resulting in stronger and shorter C–H bonds that...
711