Microwave-Absorbing Foams with Adjustable Absorption Frequency and Structural Coloration.

Nano Lett

Center for Advanced Studies in Precision Instruments, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan 570228, China.

Published: March 2024

Microwave-absorbing materials with regulatable absorption frequency and optical camouflage hold great significance in intelligent electronic devices and advanced stealth technology. Herein, we present an innovative microwave-absorbing foam that can dynamically tune microwave absorption frequencies via a simple mechanical compression while in parallel enabling optical camouflage over broad spectral ranges by adjusting the structural colors. The vivid colors spanning different color categories generated from thin-film interference can be precisely regulated by adjusting the thickness of the conformal TiO coatings on Ni/melamine foam. Enhanced interfacial and defect-induced polarizations resulting from the introduction of TiO coating synergistically contribute to the dielectric attenuation performance. Consequently, such a foam exhibits exceptional microwave absorption capabilities, and the absorption frequency can be dynamically tuned from the S band to the Ku band by manipulating its compression ratio. Additionally, simulation calculations validate the adjustable electromagnetic wave loss behavior, offering valuable insights for the development of next-generation intelligent electromagnetic devices across diverse fields.

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.nanolett.3c05006DOI Listing

Publication Analysis

Top Keywords

absorption frequency
12
optical camouflage
8
microwave absorption
8
absorption
5
microwave-absorbing foams
4
foams adjustable
4
adjustable absorption
4
frequency structural
4
structural coloration
4
coloration microwave-absorbing
4

Similar Publications

Sarcoglycanopathies are rare forms of severe muscular dystrophies currently without a therapy. Mutations in sarcoglycan (SG) genes cause the reduction or absence of the SG-complex, a tetramer located in the sarcolemma that plays a protective role during muscle contraction. Missense mutations in SGCA, which cause α-sarcoglycanopathy, otherwise known as LGMD2D/R3, lead to folding defective forms of α-SG that are discarded by the cell quality control.

View Article and Find Full Text PDF

The development of highly active and stable cathodes in alkaline solutions is crucial for promoting the commercialization of anion exchange membrane (AEM) electrolyzers, yet it remains a significant challenge. Herein, we synthesized atomically dispersed CoP moieties (CoP-SSC) immobilized on ultrathin carbon nanosheets via a phosphidation exfoliation strategy at medium temperature. The thermodynamic formation process of the Co-P moieties was elucidated using X-ray absorption spectroscopy (XAS) and theoretical calculations.

View Article and Find Full Text PDF

Transitions seen in the electric properties of water-absorbable poly(2,5-benzimidazole) (ABPBI) films were confirmed by electric conductivity, dielectric constant, and time-domain nuclear magnetic resonance (NMR) measurements. The electric resistance of the films was measured at room temperature using a high-resistance meter, and the dielectric constant at room temperature was measured using an LCR meter in the frequency range of 90 Hz to 8 MHz. The water absorption ratio at equilibrium absorption for the films was 37%, which corresponded to a volume fraction of water of 0.

View Article and Find Full Text PDF

Acoustic, Mechanical, and Thermal Characterization of Polyvinyl Acetate (PVA)-Based Wood Composites Reinforced with Beech and Oak Wood Fibers.

Polymers (Basel)

January 2025

Research Laboratory for Sustainable Development and Health, Department of Applied Physics, Faculty of Sciences and Technics, Cadi Ayyad University, Marrakesh 40000, Morocco.

Considering the growing need for developing ecological materials, this study investigates the acoustic, mechanical, and thermal properties of wood composites reinforced with beech or oak wood fibres. Scanning electron microscopy (SEM) revealed a complex network of interconnected pores within the composite materials, with varying pore sizes contributing to the material's overall properties. Acoustic characterization was conducted using a two-microphone impedance tube.

View Article and Find Full Text PDF

This paper experimentally investigates the impact response of composite laminates made with conventional and bio-based epoxy resin. Drop tower impact tests were conducted at varying energy levels, including repeated low-energy impacts, to evaluate perforation resistance. The laminates' residual strength and damage tolerance were assessed using the Damage Index (DI) and by analysing the resonance frequency variations through the Impulse Excitation Technique (IET).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!