Developing carbon encapsulated magnetic composites with rational design of microstructure for achieving high-performance electromagnetic wave (EMW) absorption in a facile, sustainable, and energy-efficiency approach is highly demanded yet remains challenging. Here, a type of N-doped carbon nanotube (CNT) encapsulated CoNi alloy nanocomposites with diverse heterostructures are synthesized via the facile, sustainable autocatalytic pyrolysis of porous CoNi-layered double hydroxide/melamine. Specifically, the formation mechanism of the encapsulated structure and the effects of heterogenous microstructure and composition on the EMW absorption performance are ascertained. With the presence of melamine, CoNi alloy emerges its autocatalysis effect to generate N-doped CNTs, leading to unique heterostructure and high oxidation stability. The abundant heterogeneous interfaces induce strong interfacial polarization to EMWs and optimize impedance matching characteristic. Combined with the inherent high conductive and magnetic loss capabilities, the nanocomposites accomplish a high-efficiency EMW absorption performance even at a low filling ratio. The minimum reflection loss of -84.0 dB at the thickness of 3.2 mm and a maximum effective bandwidth of 4.3 GHz are obtained, comparable to the best EMW absorbers. Integrated with the facile, controllable, and sustainable preparation approach of the heterogenous nanocomposites, the work shows a great promise of the nanocarbon encapsulation protocol for achieving lightweight, high-performance EMW absorption materials.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/smll.202302686 | DOI Listing |
Small
January 2025
College of Chemical Engineering, Fuzhou University, Fuzhou, Fujian, 350116, China.
The development of diverse microstructures has substantially contributed to recent progress in high-performance electromagnetic wave (EMW) absorption materials, providing a versatile platform for the modulation of absorption properties. Exploring multidimensional microstructures and developing tailored and gentle strategies for their precise optimization can substantially address the current challenges posed by relatively unclear underlying mechanisms. Here, a series of 2D/1D heterogeneous NiO@PPy composites featuring hollow hierarchical microstructures are successfully synthesized using a straightforward strategy combining sacrificial templating with chemical oxidative polymerization.
View Article and Find Full Text PDFSmall
January 2025
National Engineering Lab for Textile Fiber Materials & Processing Technology, Zhejiang Sci-Tech University, Hangzhou, 310018, P. R. China.
2D materials feature large specific surface areas and abundant active sites, showing great potential in energy storage and conversion. However, the dense, stacked structure severely restricts its practical application. Inspired by the structure of bamboo in nature, hollow interior and porous exterior wall, hollow MXene aerogel fiber (HA-TiCT fiber) is proposed.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
Institute of Zhejiang University - Quzhou, No. 99 Zheda Road, Quzhou 324000, China; Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China. Electronic address:
The trichloroethylene production industry generates high-boiling-point solid residues during rectification, which contain high concentrations of chlorinated contaminants, particularly hexachlorobutadiene (HCBD). Traditionally, these distillation residues are managed through co-incineration or landfilling, leading to environmental and economic challenges. In this study, we present a rapid and environmentally friendly electrothermal approach for both detoxifying and upcycling distillation residue into graphene-based electromagnetic wave (EMW) absorbing materials.
View Article and Find Full Text PDFSmall
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 PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!