writer：?Chenhao Wei, Lingzi Shi, Maoqing Li*, Mukun He, Mengjie Li, Xinrui Jing, Panbo Liu and Junwei Gu*
keywords：electromagnetic wave attenuation
source：期刊
specific source：Journal of Materials Science & Technology
Issue time：2023年

Chenhao Wei, Lingzi Shi, Maoqing Li*, Mukun He, Mengjie Li, Xinrui Jing, Panbo Liu and Junwei Gu*. Hollow engineering of sandwich NC@Co/NC@MnO₂ composites toward strong wideband electromagnetic wave attenuation. Journal of Materials Science & Technology, 2024, 175: 194-203. 2023IF=10.9.

https://doi.org/10.1016/j.jmst.2023.08.020

Abstract

Multiple hetero-interfaces would strengthen interfacial polarization and boost electromagnetic wave absorption, but still remain the formidable challenges in decreasing filler loadings. Herein, sandwich NC@Co/NC@MnO₂ composites with hollow cavity, multiple hetero-interfaces, and hierarchical structures have been fabricated via the cooperative processes of self-sacrifice strategy and sequential hydrothermal reaction. In the sandwich composites, middle magnetic components (Co/NC) are wrapped by inner N-doped carbon (NC) matrix and outer hierarchical MnO2 nanosheets. Importantly, hollow engineering of sandwich composites with multiple hetero-interfaces greatly facilitates the enhancement of absorption bandwidth without sacrificing the absorption intensity. The maximum reflection loss of sandwich NC@Co/NC@MnO2 composites reaches -44.8 dB at 2.5 mm and the effective bandwidths is achieved as wide as 9.6 GHz at 2.3 mm. These results provide us a new insight into preparing efficient electromagnetic wave absorbers by interface engineering and hollow construction.

多异质界面有利于增强材料的界面极化效应和电磁波吸收特性，但在减少填料填充量方面仍面临着艰巨的挑战。本论文通过牺牲模板法和水热反应的协同制备了兼具多异质界面和空腔结构的三明治夹层NC@Co/NC@MnO2复合材料。中间层的磁性组分（Co/NC）被内层的掺氮碳（NC）和外层的二氧化锰纳米片包裹，该异质界面和空腔结构使材料在较低填充量下实现了对电磁波吸强度收的扩宽。当厚度为2.5 mm时，三明治夹层NC@Co/NC@MnO2复合材料的最大反射损耗为-44.8 dB，有效带宽在2.3 mm处达到9.6 GHz。该结果为利用界面工程和空心结构制备高效电磁波吸收剂提供了一种新的思路。