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Recently, the sustainable utilization of waste resources has become a low-cost and effective strategy to design high-performance functional materials to solve the increasingly serious environmental pollution problem. Herein, the flexible and highly stretchable polyurethane (PU) composite foams assisted by one-dimensional carbon nanotubes (CNTs) and zero-dimensional Fe3O4 were fabricated using waste tire rubbers (WTRs) as reinforcements during a simple self-foaming process. The collaborative introduction of conductive CNTs, magnetic Fe3O4, and WTRs with three-dimensional cross-linked structures enabled the construction of an efficient electronic transmission path and heterointerfaces inside the composite foam. The resulting composite foam possessed a desired minimum reflection loss (RLmin) of −47.43 dB, and also exhibited superior mechanical properties with a tensile strength of >3 MPa and multiple tensile deformation recovery abilities. In addition, increasing the temperature could significantly improve the electromagnetic wave absorption performance of the composite foam. This comprehensive composite foam derived from WTRs has shown a promising development potential for using waste materials to relieve electromagnetic pollution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultra-flexible bimetallic nanowire decorated foams via facile dip-coating method. • An ultra-low filler content of 0.22 vol% for high performances. • Effective microwave absorption of −69.61 dB with ultra-wide absorption bandwidth. • Integrated multi-functional applications in one. Nowadays, functional electronic devices with excellent flexibility and thermal management capability for effective electromagnetic wave absorption are urgently in demand. Herein, a novel and highly flexible silver nanowire (AgNW)/iron nanowire (FeNW) decorated melamine composite foam (AgFe-MF) was prepared via simple dip-coating process. Owing to optimal impedance matching, synergistic dielectric and magnetic losses as well as three-dimensional porous structure, the AgFe-MF with an ultra-low filler content (0.22 vol%) exhibited an outstanding minimum reflection loss of −69.61 dB, and the best effective absorption bandwidth (EAB) could reach up to 6.37 GHz. Importantly, the EAB of long-time working AgFe-MF was enhanced to 7.01 GHz after 1000 compress-release cycles under 40 % strain. Besides, it also featured considerate Joule heating capacity and achieved a saturation temperature of over 85.7 ℃ under 2.6 V voltage. The impressive thermal isolation and long-term stability ensured the safety used as portable heater. Therefore, this work will provide a vital slight for fabricating smart wearable electronic devices with integrated anti-electromagnetic radiation and personalized thermal management performances towards potential thermal and health threats. [ABSTRACT FROM AUTHOR]

[Display omitted] • Construct multi-scale architectures from 0D to 2D with abundant heterostructures. • Enhanced microwave absorption of −67 dB with ultrabroad absorption bandwidth. • Rich heterogeneous interfaces and synergistic multiple loss mechanisms for EWA. Two-dimensional (2D) MXene has attracted vast attention in electromagnetic wave absorption (EWA), but there remains a contradiction between maintaining impedance matching and enhancing dielectric loss. Herein, the multi-scale architectures of ecoflex/2D MXene (Ti 3 C 2 T x)@zero-dimensional CoNi sphere@one-dimensional carbon nanotube composite elastomers were successfully constructed by simple liquid-phase reduction and thermo-curing method. The binding between the hybrids as fillers and ecoflex as a matrix greatly enhanced the EWA capability of the obtained composite elastomer and improved its mechanical properties. Owing to its good impedance matching, abundant heterostructures, and synergistic electrical and magnetic losses, this elastomer exhibited an excellent minimum reflection loss of −67 dB at 9.46 GHz under a thickness of 2.98 mm. In addition, its ultrabroad effective absorption bandwidth reached 6.07 GHz. This achievement will pave the way for the exploitation of multi-dimensional heterostructures as high-performance electromagnetic absorbers with superior EWA ability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel wheat-like Ni-coated core–shell silver nanowire using facile one-pot method. • High-efficiency microwave absorption of −61.1 dB with wide absorption bandwidth. • Synergistic effect of unique structure and multiple loss mechanisms for EWA. • Long-term operational stability for three months. Nowadays, developing high-performance electromagnetic functional materials to eliminate the ever-increasing electromagnetic pollution problem is necessary for the complex electromagnetic environment. However, the materials with high electrical conductivity are prone to secondary electromagnetic pollution due to interface impedance mismatching. Herein, the wheat-like electrically conductive and magnetic silver nanowire@nickle (AgNW@Ni) composites were fabricated via a one-pot in-situ growth method. The electromagnetic properties of the composites could be regulated by adjusting different ratios of precursors, resulting in various morphological features of the nanowire as the core with different Ni shell thicknesses. When the Ag and Ni molar ratio was 1:1.1, the AgNW@Ni composite exhibited the optimal minimum reflection loss (RL min) of −61.1 dB with an adequate effective absorption bandwidth (EAB) of 4.06 GHz owing to good impedance matching, abundant heterostructures, and synergistic electrical and magnetic losses. Even after three months, it still maintained an acceptable RL min value of −39.7 dB and similar EAB , demonstrating its long-term operational stability. This unique composite is expected to be applied in more actual electromagnetic protection occasions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flower-like bimetallic MOF-derived carbon composites. • Regulate structures by adjusting different precursor ratios. • High-efficiency microwave absorption of −56.89 dB with wide bandwidth of 4.7 GHz. • Synergistic effect of unique structure and electromagnetic characteristic for EWA. Recently, high-performance functional composites for electromagnetic wave absorption (EWA) with tunable nano/micro-structures have attracted extensive attention. Herein, the flower-like electrically conductive and magnetic cobalt-nickel@carbon (CoNi@C) composites derived from bimetallic metal-organic frameworks (MOFs) were fabricated via solvothermal method and pyrolysis. By adjusting the ratios of different precursors, different morphological features of composites were formed. When the molar ratio of Co and Ni was 1:2, the CoNi@C composites exhibited the optimal minimum reflection loss (RL min) of −56.89 dB at 6.7 GHz with an effective absorption bandwidth of 4.7 GHz, due to the coordinated dielectric and magnetic loss caused by the electromagnetic properties of each component as well as the interactions between the unique three-dimensional (3D) interfaces of flower-like structures that promoted the absorption and dissipation of composites for microwaves. The composites are expected to become promising candidates as high-efficiency absorbers in the electromagnetic protection field. [ABSTRACT FROM AUTHOR]

Nowadays, high-performance electromagnetic wave (EMW) absorption materials derived from low-cost biomass materials have attracted widespread attention. Herein, a novel biomass‑carbon with porous array structures derived from waste soybean dregs is prepared by a hydrothermal method combined with heat treatment using formaldehyde and KOH as activators. The as-prepared biomass‑carbon with significantly enhanced specific surface area can possess more charge transmission paths, increased multiple reflections and scattering, multiple loss modes, and improved impedance matching, leading to the improvement of EMW absorption performances. The obtained single-component biomass‑carbon without any functional fillers exhibits an effective EMW absorption capability with a wide absorption bandwidth of 4.8 GHz at a thickness of 3.5 mm. This study will provide a valuable approach for the preparation of biomass‑carbon based EMW absorption materials with controllable porous structures by the activation process. [Display omitted] • High-performance single-component biomass carbon derived from soybean dregs • Unique porous array structures formed through an activation process. • Effective EMW absorption capability with a wide absorption bandwidth of 4.8 GHz. [ABSTRACT FROM AUTHOR]

Nowadays, electromagnetic pollution caused by the development of communication technology and electronic equipment has become an urgent problem to be solved. It is an effective solution to design high-performance electromagnetic wave absorption (EWA) materials with wide-band and powerful absorption characteristics for electromagnetic protection. In this work, a multi-scale MXene/carbon nanotube@Fe 3 O 4 composite material with a heterogeneous structure was synthesized by a solvothermal method, and the high/low-frequency EWA operating bands were adjusted by component regulation. The composite material performed excellent EWA performances based on the synergistic effect of polarization loss, conductive and magnetic loss, and three-dimensional heterointerfaces. Its minimum reflection loss reached − 59.95 dB with an effective absorption bandwidth of 4.7 GHz (13.3–18 GHz), which basically covered the Ku band. Therefore, this feasible scheme is expected to provide an effective strategy for controlling military and civil electromagnetic pollution. [Display omitted] • A facile preparation method of MXene-based multiscale composites was proposed. • Military/civil EWA operating frequency bands were adjusted by component regulation. • A superior RL min value of − 59.95 dB was obtained based on complex loss mechanisms. [ABSTRACT FROM AUTHOR]

The absorption performance of broadband electromagnetic waves is of utmost importance in safeguarding diverse electronic equipment against electromagnetic wave pollution, necessitating materials with low density, thin thickness, and cost-effectiveness to be employed. This study presents the successful synthesis of biomass-derived carbon (BC) composites via the hydrothermal method, utilizing moss coated with flower-like CuS. The CuS was uniformly dispersed on BC matrix, contribute to dipole polarization relaxation. The formation of heterogeneous interfaces between CuS and the BC phase resulted in significant polarization loss. Additionally, the wrinkled BC and flower like CuS constructed by nanosheets boosted scattering of electromagnetic wave due to its large specific surface area, which can provide additional channels for charge transfer and avail dissipation of electromagnetic wave energy. With an efficient absorption bandwidth (EAB) that encompasses the whole X band, the electromagnetic waves absorption (EMA) performance of CuS/BC composites was able to reach a minimum reflection loss of − 28.8 dB. • A simple preparation method of biomass-derived carbon (BC) composites was proposed. • The wrinkled BC and flower like CuS boosted scattering of electromagnetic wave. • The CuS/BC composites reached a superior minimum reflection loss of − 28.8 dB. [ABSTRACT FROM AUTHOR]

Currently, electromagnetic interference (EMI) shielding and microwave absorption are two important means to alleviate the increasingly severe electromagnetic (EM) pollution. However, the application areas of EMI shielding and microwave absorption are quite different, so integrating these two capabilities in the same material is a great challenge. Herein, multiple-scale polyurethane (PU) composite foams (CFs) assisted by tadpole-like carbon nanotube (CNT)@Fe 3 O 4 nanocomposites were designed by a facile solvothermal and self-foaming method. By adjusting the CNT@Fe 3 O 4 loadings and ambient temperatures, the EM parameters and interface impedance matching of PU/CNT@Fe 3 O 4 CFs could be optimized, thus realizing the coexistence of EMI shielding and microwave absorption inside one same material. The resulting CF exhibited an effective minimum reflection loss (RL min) of −41.9 dB and EMI shielding effectiveness (SE) of ∼20 dB. Furthermore, the elevated temperatures within a range of −20-60 °C would stimulate the transformation of individual CF from microwave absorption towards EMI shielding capability and vice versa. This work will promote the development of intelligent EM compatible devices in the field of optional EM protection. [Display omitted] • Polyurethane composite foams assisted by multi-dimensional coral-like components • Reversibly switching microwave absorption towards EMI shielding capability • Outstanding and tunable temperature-stimulated EM protection ability [ABSTRACT FROM AUTHOR]

With the increasingly serious electromagnetic pollution, the urgent demands for electromagnetic wave absorption (EMWA) materials are gradually developing towards performance integration and multi-dimensional scales. Herein, the enoki-like carbon nanotubes (CNTs) coated with nickel particles (CNT@Ni) were synthesized by a catalytic thermal decomposition method. The resulting CNT@Ni composites exhibited excellent EMWA performances with a minimum reflection loss value of − 60.4 dB at a thickness of 2.97 mm. It benefited from the synergy of collaborative electrical and magnetic losses and hierarchical structure. The conductive pathways formed by the intertwined CNTs greatly improved the EMWA capacity of the material, enabling large amounts of electromagnetic waves to enter the material for conversion and dissipation. In addition, the inherent graphite defects and oxygen-containing groups formed on the material surface during the process of high-temperature treatment provided polarization centers for dipole polarizations. More importantly, the abundant heterogeneous interfaces enhanced the interface loss effects of the material. This simple preparation strategy of the CNT-based EMWA material will provide a design inspiration for the novel electromagnetic absorber. [Display omitted] • A simple preparation method of CNTs coated with nickel particles was proposed. • Enoki-like structures provided rich heterogeneous interfaces. • A superior RL min value of − 60.4 dB was obtained based on complex loss mechanisms. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultra-light carbon nanofiber aerogels assisted by bimetal-organic frameworks. • Enhanced microwave absorption of −66.57 dB and super-wide absorption bandwidth. • Long-term thermal stability with super-fast Joule heating (cooling) rate. Lightweight carbon-based aerogels with fast heat dissipation capability are promising electromagnetic wave absorber materials for developing integrated electronics, artificial intelligence, and human-interaction equipment under harsh thermal environments. Herein, the bimetallic (cobalt (Co) and nickel (Ni)) metal–organic frameworks (CoNi-MOFs), cellulose nanofibrils (CNFs), and aramid nanofibers (ANFs) were assembled into a conductive and magnetic CoNi@carbon/ANF/CNF carbon composite aerogel (CoNi@C/ACA) with an ultra-low density of 6.15 mg/cm3 using freeze-drying and subsequent carbonization treatment. Owing to the synergistic effects of multiple reflections inside the three-dimensional interconnected structures, abundant interfacial/dipolar polarizations, and coordinated dielectric and magnetic losses, the CoNi@C/ACA achieved a fascinating minimum reflection loss value of −66.57 dB and broad effective absorption bandwidth up to 6.3 GHz, which were characterized with an ultra-low loading of 1.8 wt%. In addition, it displayed good thermal stability with a super-fast Joule heating (cooling) rate at low driving voltages. These unique characteristics of the ultra-light CoNi@C/ACA make it a promising material for demanding applications, e.g. , electromagnetic pollution elimination and thermal management. [ABSTRACT FROM AUTHOR]