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Developing an ultimate electromagnetic (EM)-absorbing material that can not only dissipate EM energy but also convert the generated heat into electricity is highly desired but remains a significant challenge. Here, we report a hybrid Sn@C composite with a biological cell-like splitting ability to address this challenge. The composite consisting of Sn nanoparticles embedded within porous carbon would split under a cycled annealing treatment, leading to more dispersed nanoparticles with an ultrasmall size. Benefiting from an electron-transmitting but a phonon-blocking structure created by the splitting behavior, an EM wave-electricity device constructed by the optimum Sn@C composite could achieve an efficiency of EM to heat at widely used frequency region and a maximum thermoelectric figure of merit of 0.62 at 473 K, as well as a constant output voltage and power under the condition of microwave radiation. This work provides a promising solution for solving EM interference with self-powered EM devices. Materials that can harvest electromagnetic (EM) waves and harness the resulting energy would have many applications. Here, the authors present a hybrid composite that produces thermoelectricity from the heating in the EM absorption under microwave radiation.

HighlightsNiCo-LDHs successfully grow in situ on rod-like ZnO with unique structures.The interface of NiCo@C and rod-like ZnO result in interfacial polarization.The RLmin of NiCo@C/ZnO reaches − 60.97 dB with the EABmax of 6.08 GHz.The excellent performance comes from the effect of dielectric loss and magnetic loss.Layered double hydroxides (LDHs) have a special structure and atom composition, which are expected to be an excellent electromagnetic wave (EMW) absorber. However, it is still a problem that obtaining excellent EMW-absorbing materials from LDHs. Herein, we designed heterostructure NiCo-LDHs@ZnO nanorod and then subsequent heat treating to derive NiCo@C/ZnO composites. Finally, with the synergy of excellent dielectric loss and magnetic loss, an outstanding absorption performance could be achieved with the reflection loss of − 60.97 dB at the matching thickness of 2.3 mm, and the widest absorption bandwidth of 6.08 GHz was realized at 2.0 mm. Moreover, this research work provides a reference for the development and utilization of LDHs materials in the field of microwave absorption materials and can also provide ideas for the design of layered structural absorbers.

Dielectric materials with good thermal transport performance and desirable dielectric properties have significant potential to address the critical challenges of heat dissipation for microelectronic devices and power equipment under high electric field. This work reported the role of synergistic effect and interface on through-plane thermal conductivity and dielectric properties by intercalating the hybrid fillers of the alumina and boron nitride nanosheets (BNNs) into epoxy resin. For instance, epoxy composite with hybrid fillers at a relatively low loading shows an increase of around 3 times in through-plane thermal conductivity and maintains a close dielectric breakdown strength compared to pure epoxy. Meanwhile, the epoxy composite shows extremely low dielectric loss of 0.0024 at room temperature and 0.022 at 100 ℃ and 10 −1  Hz. And covalent bonding and hydrogen-bond interaction models were presented for analyzing the thermal conductivity and dielectric properties.

HighlightsHeterogeneous interface engineering is designed by electrospinning.The introduction of Co3SnC0.7 nanoparticles increased the loss mechanism.Enhanced electromagnetic loss and improved impedance matching are achieved.The absorbers exhibit high-efficient electromagnetic wave absorption performance.Application of novel radio technologies and equipment inevitably leads to electromagnetic pollution. One-dimensional polymer-based composite membrane structures have been shown to be an effective strategy to obtain high-performance microwave absorbers. Herein, we reported a one-dimensional N-doped carbon nanofibers material which encapsulated the hollow Co3SnC0.7 nanocubes in the fiber lumen by electrospinning. Space charge stacking formed between nanoparticles can be channeled by longitudinal fibrous structures. The dielectric constant of the fibers is highly related to the carbonization temperature, and the great impedance matching can be achieved by synergetic effect between Co3SnC0.7 and carbon network. At 800 °C, the necklace-like Co3SnC0.7/CNF with 5% low load achieves an excellent RL value of − 51.2 dB at 2.3 mm and the effective absorption bandwidth of 7.44 GHz with matching thickness of 2.5 mm. The multiple electromagnetic wave (EMW) reflections and interfacial polarization between the fibers and the fibers internal contribute a major effect to attenuating the EMW. These strategies for regulating electromagnetic performance can be expanded to other electromagnetic functional materials which facilitate the development of emerging absorbers.

Bioderived carbon materials have garnered considerable interest in the fields of microwave absorption and shielding due to their reproducibility and environmental friendliness. In this study, KOH was evenly distributed on biomass Tremella using the swelling induction method, leading to the preparation of a three-dimensional network-structured hierarchical porous carbon (HPC) through carbonization. The achieved microwave absorption intensity is robust at −47.34 dB with a thin thickness of 2.1 mm. Notably, the widest effective absorption bandwidth, reaching 7.0 GHz (11–18 GHz), is attained at a matching thickness of 2.2 mm. The exceptional broadband and reflection loss performance are attributed to the 3D porous networks, interface effects, carbon network defects, and dipole relaxation. HPC has outstanding absorption characteristics due to its excellent impedance matching and high attenuation constant. The uniform pore structures considerably optimize the impedance-matching performance of the material, while the abundance of interfaces and defects enhances the dielectric loss, thereby improving the attenuation constant. Furthermore, the impact of carbonization temperature and swelling rate on microwave absorption performance was systematically investigated. This research presents a strategy for preparing absorbing materials using biomass-derived HPC, showcasing considerable potential in the field of electromagnetic wave absorption.

Transition metal dichalcogenides (TMDs) show great advantages in electromagnetic wave (EMW) absorption due to their unique structure and electrical properties. Tremendous research works on TMD-based EMW absorbers have been conducted in the last three years, and the comprehensive and systematical summary is still a rarity. Therefore, it is of great significance to elaborate on the interaction among the morphologies, structures, phases, components, and EMW absorption performances of TMD-based absorbers. This review is devoted to analyzing TMD-based absorbers from the following perspectives: the EMW absorption regulation strategies of TMDs and the latest progress of TMD-based hybrids as EMW absorbers. The absorption mechanisms and component-performance dependency of these achievements are also summarized. Finally, a straightforward insight into industrial revolution upgrading in this promising field is proposed.

HighlightsNiCo/C aerogel was prepared by pyrolysis carbonization self-assembly of NiCo- metal–organic frameworks (MOFs).The assembly mechanism of MOF aerogel was studied by adjusting the ratio of metal ion /BTC. Aerogel combines hydrophobic, lightweight, self-cleaning, and electromagnetic wave absorption properties.Although multifunctional aerogels are expected to be used in applications such as portable electronic devices, it is still a great challenge to confer multifunctionality to aerogels while maintaining their inherent microstructure. Herein, a simple method is proposed to prepare multifunctional NiCo/C aerogels with excellent electromagnetic wave absorption properties, superhydrophobicity, and self-cleaning by water-induced NiCo-MOF self-assembly. Specifically, the impedance matching of the three-dimensional (3D) structure and the interfacial polarization provided by CoNi/C as well as the defect-induced dipole polarization are the primary contributors to the broadband absorption. As a result, the prepared NiCo/C aerogels have a broadband width of 6.22 GHz at 1.9 mm. Due to the presence of hydrophobic functional groups, CoNi/C aerogels improve the stability in humid environments and obtain hydrophobicity with large contact angles > 140°. This multifunctional aerogel has promising applications in electromagnetic wave absorption, resistance to water or humid environments.

Wireless energy-responsive systems provide a foundational platform for powering and operating intelligent devices. However, current electronic systems relying on complex components limit their effective deployment in ambient environment and seamless integration of energy harvesting, storage, sensing, and communication. Here, we disclose a coupling effect of electromagnetic wave absorption and moist-enabled generation on carrier transportation and energy interaction regulated by ionic diode effect. As demonstration, a wireless energy interactive system is established for electromagnetic-moist coupled energy harvesting and signal transmission through highly integrated polyelectrolyte/conjugated conductive polymer bilayer ionic diode films as dynamic energy-switching carriers. The gradient distribution of ions within the films, excited by moist energy, enables the ionic rectification and further endows the films with electromagnetic energy harvesting capability. In turn, the absorbed electromagnetic energy drives the directional migration of charge carriers and internal ionic current. By rationally regulating the electrolyte and dielectric properties of ionic diodes, it becomes feasible to control targeted electric signals and energy outputs under coupled electromagnetic-moist environment. This work is a step towards enabling enhanced smart interactivities for wirelessly driven flexible electronics. Wireless energy-responsive systems are essential for intelligent devices. This study demonstrates an electromagnetic-moist coupling effect for energy harvesting and signal transmission using fabricated ionic diode films, showing improved performance and potential for practical applications.

HighlightsElectrospinning combined with structural engineering to construct 0D@2D@1D hierarchical heterogeneous interfaces.A “mechanical response” model was constructed to explain the stress transfer mechanism of fibrous membranes with 2D@1D structures.The “One for All” fibrous membrane combines excellent flexibility, mechanical properties, waterproof, and electromagnetic protection.The development of wearable multifunctional electromagnetic protective fabrics with multifunctional, low cost, and high efficiency remains a challenge. Here, inspired by the unique flower branch shape of “Thunberg’s meadowsweet” in nature, a nanofibrous composite membrane with hierarchical structure was constructed. Integrating sophisticated 0D@2D@1D hierarchical structures with multiple heterointerfaces can fully unleash the multifunctional application potential of composite membrane. The targeted induction method was used to precisely regulate the formation site and morphology of the metal–organic framework precursor, and intelligently integrate multiple heterostructures to enhance dielectric polarization, which improves the impedance matching and loss mechanisms of the electromagnetic wave absorbing materials. Due to the synergistic enhancement of electrospinning-derived carbon nanofiber “stems”, MOF-derived carbon nanosheet “petals” and transition metal selenide nano-particle “stamens”, the CoxSey/NiSe@CNSs@CNFs (CNCC) composite membrane obtains a minimum reflection loss value (RLmin) of -68.40 dB at 2.6 mm and a maximum effective absorption bandwidth (EAB) of 8.88 GHz at a thin thickness of 2.0 mm with a filling amount of only 5 wt%. In addition, the multi-component and hierarchical heterostructure endow the fibrous membrane with excellent flexibility, water resistance, thermal management, and other multifunctional properties. This work provides unique perspectives for the precise design and rational application of multifunctional fabrics.

Harvesting largely ignored and wasted electromagnetic (EM) energy released by electronic devices and converting it into direct current (DC) electricity is an attractive strategy not only to reduce EM pollution but also address the ever-increasing energy crisis. Here we report the synthesis of nanoparticle-templated graphene with monodisperse and staggered circular nanopores enabling an EM–heat–DC conversion pathway. We experimentally and theoretically demonstrate that this staggered nanoporous structure alters graphene’s electronic and phononic properties by synergistically manipulating its intralayer nanostructures and interlayer interactions. The staggered circular nanoporous graphene exhibits an anomalous combination of properties, which lead to an efficient absorption and conversion of EM waves into heat and in turn an output of DC electricity through the thermoelectric effect. Overall, our results advance the fundamental understanding of the structure–property relationships of ordered nanoporous graphene, providing an effective strategy to reduce EM pollution and generate electric energy. The electromagnetic (EM) energy released by electronic devices in the environment is largely wasted and contributes to EM pollution. Here, the authors report the synthesis of staggered circular nanoporous graphene enabling the absorption and conversion of EM waves into electricity via the thermoelectric effect.