Modified negative permittivity and X-band microwave absorption in polyvinyl Alcohol–MWCNT metacomposites

IF 6.5 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composites Communications Pub Date : 2024-11-13 DOI:10.1016/j.coco.2024.102161

Swetha P. , Sindhu Swaminathan , Kishore Sridharan , Mohamed Shahin T.H. , Faheema S.

{"title":"Modified negative permittivity and X-band microwave absorption in polyvinyl Alcohol–MWCNT metacomposites","authors":"Swetha P. , Sindhu Swaminathan , Kishore Sridharan , Mohamed Shahin T.H. , Faheema S.","doi":"10.1016/j.coco.2024.102161","DOIUrl":null,"url":null,"abstract":"<div><div>Metacomposite films with modifiable negative permittivity are promising for wearable cloaking, sensing, electromagnetic interference shielding, and microwave absorption. The purpose of this study is to fabricate metacomposite films composed of polyvinyl alcohol (PVA) and multi-walled carbon nanotubes (MWCNTs) and demonstrate control of permittivity by varying MWCNT concentration. Drude-Lorentz and Drude models show negative permittivity behaviour as the MWCNT content increases. The Drude-Lorentz and Drude models confirm that at 1 wt% MWCNT loading, percolation occurs, leading to increased conductivity and a transition from positive to negative permittivity (−9 at 10 kHz and −200 at 34 kHz). Drude's model predicts negative permittivity across the entire frequency range of PVA with 3 wt% MWCNT. Metacomposite films exhibit electrical percolation, conductivity switching, permittivity shift, and capacitive-to-inductive transitions. These composites also demonstrate excellent X-band microwave absorption properties (up to −50 dB reflection loss) and a shielding efficiency of 22 dB, suggesting an absorption-dominated shielding mechanism.</div></div>","PeriodicalId":10533,"journal":{"name":"Composites Communications","volume":"52 ","pages":"Article 102161"},"PeriodicalIF":6.5000,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Composites Communications","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2452213924003528","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, COMPOSITES","Score":null,"Total":0}

引用次数: 0

Abstract

Metacomposite films with modifiable negative permittivity are promising for wearable cloaking, sensing, electromagnetic interference shielding, and microwave absorption. The purpose of this study is to fabricate metacomposite films composed of polyvinyl alcohol (PVA) and multi-walled carbon nanotubes (MWCNTs) and demonstrate control of permittivity by varying MWCNT concentration. Drude-Lorentz and Drude models show negative permittivity behaviour as the MWCNT content increases. The Drude-Lorentz and Drude models confirm that at 1 wt% MWCNT loading, percolation occurs, leading to increased conductivity and a transition from positive to negative permittivity (−9 at 10 kHz and −200 at 34 kHz). Drude's model predicts negative permittivity across the entire frequency range of PVA with 3 wt% MWCNT. Metacomposite films exhibit electrical percolation, conductivity switching, permittivity shift, and capacitive-to-inductive transitions. These composites also demonstrate excellent X-band microwave absorption properties (up to −50 dB reflection loss) and a shielding efficiency of 22 dB, suggesting an absorption-dominated shielding mechanism.

查看原文本刊更多论文

聚乙烯醇-MWCNT 元复合材料中的改性负介电常数和 X 波段微波吸收率

具有可调负介电常数的元复合薄膜有望用于可穿戴隐形、传感、电磁干扰屏蔽和微波吸收。本研究的目的是制作由聚乙烯醇（PVA）和多壁碳纳米管（MWCNTs）组成的元复合薄膜，并演示通过改变 MWCNT 的浓度来控制介电常数。随着 MWCNT 含量的增加，Drude-Lorentz 和 Drude 模型显示出负的介电常数行为。Drude-Lorentz 和 Drude 模型证实，当 MWCNT 含量为 1 wt% 时，会发生渗滤，从而导致电导率增加，介电常数从正值过渡到负值（10 kHz 时为 -9，34 kHz 时为 -200）。根据 Drude 的模型预测，含有 3 wt% MWCNT 的 PVA 在整个频率范围内的介电常数为负。金属复合薄膜表现出电渗、电导切换、介电常数偏移和电容到电感的转变。这些复合材料还表现出优异的 X 波段微波吸收特性（反射损耗高达 -50 dB）和 22 dB 的屏蔽效率，表明其屏蔽机制以吸收为主。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Composites Communications Materials Science-Ceramics and Composites

CiteScore

12.10

自引率

10.00%

发文量

340

审稿时长

36 days

期刊介绍： Composites Communications (Compos. Commun.) is a peer-reviewed journal publishing short communications and letters on the latest advances in composites science and technology. With a rapid review and publication process, its goal is to disseminate new knowledge promptly within the composites community. The journal welcomes manuscripts presenting creative concepts and new findings in design, state-of-the-art approaches in processing, synthesis, characterization, and mechanics modeling. In addition to traditional fiber-/particulate-reinforced engineering composites, it encourages submissions on composites with exceptional physical, mechanical, and fracture properties, as well as those with unique functions and significant application potential. This includes biomimetic and bio-inspired composites for biomedical applications, functional nano-composites for thermal management and energy applications, and composites designed for extreme service environments.