A series of CoNi/C nanocomposite fibers with different Co and Ni ratios were successfully prepared by electrospinning and carbonization techniques for the study of electromagnetic microwave (EMW) absorbing materials. We systematically studied the influence of Co and Ni content on the microstructure, chemical composition, magnetic properties, and EMW absorption characteristics of the samples. The results showed that CoNi/C nanocomposite fibers obtained excellent EMW absorption ability through the reasonable design of the composition, and the Co/Ni ratio significantly affected the microstructure and EMW absorption performance. When the Co/Ni ratio was 1/3, the minimum reflection loss (RL) is -71.2 dB (2.4 mm, 13.4 GHz), and the maximum effective absorption bandwidth (EAB, RL<-10 dB) is up to 5.9 GHz (2.2 mm, 12.1-18 GHz), covering almost the entire Ku band. This study demonstrated the enormous potential of one-dimensional structure in the field of EMW absorption. In addition, the CoNi/C nanocomposite fiber synthesized using a straightforward and low-cost method not only has excellent EMW absorption performance but also has the potential for practical application. The results of this study provide a simple and effective approach for designing high-performance EMW absorbing materials.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jcis.2023.09.009 | DOI Listing |
Small
December 2024
Shaanxi Key Laboratory of Macromolecular Science and Technology, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, 710072, P. R. China.
The demand for temperature-robust electromagnetic wave (EMW) absorption materials is escalating due to the varying operational temperatures of electronic devices, which can easily soar up to 100 °C, significantly affecting EMW interference management. Traditional absorbers face performance degradation across broad temperature ranges due to alterations in electronic mobility and material impedance. This study presented a novel approach by integrating semiconductor metal-organic frameworks (SC-MOFs) with paraffin wax (PW), leveraging the precise control of interlayer spacing in SC-MOFs for electron mobility regulation and the introduction of paraffin wax for temperature-inert electromagnetic properties.
View Article and Find Full Text PDFMaterials (Basel)
November 2024
School of Safety Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
The roles of dielectric materials in adjusting the electromagnetic wave (EMW) absorption performance of an EMW absorber are as crucial as the EMW absorbents. The commonly used cement-based materials, such as mortar, are typical composites of multiple dielectric materials, such as quartz sand and air in the pores. This study investigates the EMW-absorption performances within the frequency range of 2 GHz to 18 GHz of cement paste and mortar samples with different sand-to-cement ratios (S/C), water-to-cement ratios (W/C), and thicknesses.
View Article and Find Full Text PDFSmall Methods
November 2024
Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, School of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang, 330063, P. R. China.
MXenes are 2D materials known for their unique electromagnetic wave absorption (EMWA) properties arising from their varied composition and structure. In this study, a one-step ice-assisted process is utilized to directly transform 2D MXene into 3D single-layer MXene aerogels (SMAs). Furthermore, the interlayer spacing of the SMAs is optimized by incorporating helical carbon nanotubes (HCNTs).
View Article and Find Full Text PDFSmall
November 2024
MOE Key Laboratory of Material Physics and Chemistry under Extraordinary, School of Physical Science and Technology, Northwestern Polytechnical University, Xi'an, 710072, P. R. China.
Dual atoms (DAs), characterized by flexible structural tunability and high atomic utilization, hold significant promise for atom-level coordination engineering. However, the rational design with high-density heterogeneous DAs pairs to promote electromagnetic wave (EMW) absorption performance remains a challenge. In this study, high-density Ni─Cu pairs coupled DAs absorbers are precisely constructed on a nitrogen-rich carbon substrate, achieving an impressive metal loading amount of 4.
View Article and Find Full Text PDFMaterials (Basel)
November 2024
Shandong Jinhong New Material Co., Ltd., Weifang 262100, China.
With the increasing demand for effective electromagnetic wave (EMW) absorbers due to the proliferation of electronic devices and 5G communication systems, traditional wave-absorbing materials can no longer meet the current requirements. Thus, this research introduces a three-dimensional (3D) composite material consisting of PMMA@Mxene@Co₃O₄ microspheres, prepared through in situ self-assembly and hydrothermal growth. The strong electrical conductivity of Mxene, combined with the magnetic loss of Co₃O₄, ensures enhanced dielectric-magnetic synergy, leading to excellent EMW absorption.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!