固定点原子调节工程低厚宽带宽带微波吸收
Yuetong Qian1, Zhengchen Wu2, Xiaowei Lv2
1Materials Genome Institute, Shanghai University, Shanghai, 200444, China.
Small (Weinheim an der Bergstrasse, Germany)
|May 14, 2024
概括
在硫化物中用Fe和Ni进行原子兴奋剂增强了微波吸收特性. 这项研究精确地控制了兴奋剂部位,以改善介电极化和减少先进材料中的反射损失.
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:
- 原子兴奋剂对于调整材料性质至关重要,但控制兴奋剂部位和度仍然具有挑战性.
- 了解兴奋剂和电特性之间的关系是开发先进材料的关键.
- 螺旋相金属硫化物,如Co9S8,对微波吸收应用具有前景.
研究的目的:
- 开发一种策略,使用Fe和Ni来精确地对Co9S8中的A位点离子进行原子规模的兴奋剂.
- 调查受控兴奋剂如何影响晶体结构,电子能量再分配和介电性质.
- 为了提高Co9S8纳米材料的微波吸收性能.
主要方法:
- 开发了一个原子规模的固定点兴奋剂策略.
- 引入Fe和Ni作为A位点离子补充剂到Co9S8晶格中.
- 分析了局部格子扭曲,应变度和电子能量再分配的变化.
- 评估了微波吸收特性,包括介电极化,有效吸收带宽 (EAB) 和最小反射损失 (RLmin).
主要成果:
- 精确控制的兴奋剂场所引入了局部格子扭曲和应变度.
- 调整的电子能量再分配加强了电子相互作用,并增强了高频介电极化 (在12 GHz时从10.5到12.5的ε').
- 用铁添加的Co9S8在1.7毫米厚度时,有效吸收带宽增加了5%,最小反射损失 (RLmin = -46 dB,EAB = 5.8 GHz) 提高了26%.
结论:
- 原子尺度固定点兴奋剂是定制纳米材料介电性能的有效方法.
- 这种方法为设计高性能微波吸收材料提供了宝贵的见解.
- 开发的兴奋剂策略为先进的材料设计提供了一个有前途的途径.
相关概念视频
Standing Waves in a Cavity
912
A household microwave and lasers are examples of standing electromagnetic waves in a cavity. When two conducting metal plates are placed parallel at the nodal planes, it creates a cavity where standing waves are formed. The cavity between the two planes is analogous to a stretched string held at the points x = 0 and x = L. Here, the distance 'L' between the two planes must be an integer multiple of half of the wavelength. The wavelengths that satisfy this condition are given by:
912
Atomic Absorption Spectroscopy: Interference
742
Interference leads to systematic error in atomic absorption (AA) measurements by enhancing or diminishing the analytical signal or the background. These interferences can be grouped into three main categories: spectral interference, chemical interference, and physical interference.
Spectral interference occurs when signals from other elements or molecules overlap with the analyte signal, falsely elevating or masking the analyte's absorbance. This interference can be corrected using Zeeman,...
Spectral interference occurs when signals from other elements or molecules overlap with the analyte signal, falsely elevating or masking the analyte's absorbance. This interference can be corrected using Zeeman,...
742
Atomic Absorption Spectroscopy: Radiation and Light Sources
386
Atomic absorption spectroscopy (AAS) relies on the Beer-Lambert law, which requires that the radiation source emits a narrow range of wavelengths to match the absorption characteristics of the analyte atom. The primary criteria for choosing an appropriate radiation source in AAS is to provide a precise and intense emission at specific wavelengths that will allow accurate detection of the analyte.
Two common narrow-range 'line' sources used in AAS are hollow-cathode lamps (HCLs) and...
Two common narrow-range 'line' sources used in AAS are hollow-cathode lamps (HCLs) and...
386
Atomic Absorption Spectroscopy: Instrumentation
623
An atomic absorption spectrophotometer (AAS) comprises several components: a radiation source, an atomizer, a monochromator, and a detector. The radiation source can be a hollow-cathode lamp (HCL) or an electrodeless-discharge lamp (EDL), both of which provide a narrow emission line of the required wavelength. However, some instruments use continuum sources and high-resolution monochromators to achieve a narrow range of radiation.
The atomizer used in AAS can be either a flame atomizer or an...
The atomizer used in AAS can be either a flame atomizer or an...
623
Atomic Absorption Spectroscopy: Lab
348
For AAS measurements, samples must be introduced as clear solutions, often requiring extensive preliminary treatment to dissolve materials like soils, animal tissues, and minerals. Common methods for sample preparation include treatment with hot mineral acids, wet ashing, combustion in closed containers, high-temperature ashing, or fusion with reagents.
Solutions containing organic solvents, such as low-molecular-mass alcohols, esters, or ketones, enhance absorbances by increasing...
Solutions containing organic solvents, such as low-molecular-mass alcohols, esters, or ketones, enhance absorbances by increasing...
348


