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[Display omitted] Advanced microwave absorption (MA) materials have attracted widespread attention to meet the challenges of electromagnetic (EM) pollution. Herein, MgFe 2 O 4 /MgO/C fibers were successfully prepared via electrospinning technology and carbonization, and their surfaces were coated by MoS 2 via hydrothermal method. The EM wave absorption performance of composites was enhanced due to the introduction of MoS 2. The results showed that the EM wave absorption performance of MgFe 2 O 4 /MgO/C could not meet the requirements due to low dielectric loss and poor impedance matching. The performance of the composites was improved after coating of MoS 2 , which showed the strong wave absorption capability and the broad absorption bandwidth. The optimal reflection loss (RL) is −56.94 dB at 9.5 GHz and the effective absorption bandwidth is 3.9 GHz (8.08–11.98 GHz) with a thickness of 2.7 mm. The excellent MA performance can be mainly attributed to excellent synergistic effect between MgFe 2 O 4 /MgO/C and MoS 2. Furthermore, MoS 2 also contributes to dielectric loss and ideal impedance matching. MgFe 2 O 4 /MgO/C@MoS 2 composites may be utilized for lightweight and high-efficient MA materials. [ABSTRACT FROM AUTHOR]

[Display omitted] In this work, one-dimensional (1D) ZnFe 2 O 4 @carbon@MoS 2 /FeS 2 composites were synthesized by hydrothermal method, magnetic-field-induced distillation-precipitation polymerization and high-temperature carbonization. The structure, morphology, composition, magnetic performance and electromagnetic (EM) wave absorbing properties of the composites were systematically studied. The composites show strong microwave absorption (MA) capacity with a minimum reflection loss (RL min) value of −52.5 dB at 13.2 GHz, and have an effective absorption frequency range of 10.10–15.08 GHz with a bandwidth of 4.98 GHz when the thickness is 2.23 mm. It is expected that as-synthesized 1D ZnFe 2 O 4 @carbon@MoS 2 /FeS 2 composites can be a promising EM wave absorption material. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS 2) is a transition metal sulfide that is widely used as a microwave absorption material (MAM) due to its excellent structural and physicochemical properties. MoS 2 has semiconductor properties, a large specific surface area and a large number of defects that allow it to exhibit excellent microwave loss characteristics. The lamellar MoS 2 can effectively increase the scattering and absorption of microwaves within the absorber by building a variety of different structures. The MoS 2 -based synthetic strategy, structure and properties are presented in this review. The current knowledge on the performance of MoS 2 -based MAMs is comprehensively concluded and analyzed. Moreover, the recent progress of MoS 2 -based MAMs is objectively evaluated and overviewed while the main issues and development difficulties are dissected. Therefore, MoS 2 -based composites are expected to be promising candidates as ultrathin and lightweight MAMs. • The 2D MoS 2 has special electromagnetic properties and promising applications in the field of microwave absorption. • The achievements and challenges of MoS 2 and composites are reviewed, and the preparation methods, structures and microwave absorption properties are analyzed. • The review shows the way to prepare new 2D MoS 2 -based MA materials. [ABSTRACT FROM AUTHOR]

[Display omitted] Herein, coralloid core-shell structure NiS/Ni 3 S 4 @PPy@MoS 2 nanowires were elaborately designed and successfully synthesized through a three-step route to obtain exceptional microwave absorption (MA) properties. Ni nanowires were first fabricated, and then used as the substrate to be coated with a layer of PPy. Ni chalcogenides were obtained by using Ni nanowire as sacrificial templates while growing MoS 2 nanorods by hydrothermal method. Both the one-dimensional (1D) core-shell structure and the coralloid surface generated by MoS 2 nanorods were beneficial for the attenuation of microwaves. After investigating the electromagnetic properties of different loading content absorbers (30 wt.%, 40 wt.% and 50 wt.%), it is found that the 50 wt.% loading absorber has the optimal MA performance. The minimum reflection loss (RL min) value can reach −51.29 dB at 10.1 GHz with a thickness of 2.29 mm, and the corresponding effective absorption bandwidth (EAB, RL < −10 dB) can be up to 3.24 GHz. This research provides a reference for exploiting novel high-efficient 1D absorbers in the field of MA. [ABSTRACT FROM AUTHOR]

As important functional materials for absorbing and attenuating incident electromagnetic waves, microwave absorption (MA) materials have found a wide range of applications in civil and military fields. In addition to the study of the compositions, the structural design of the MA materials is also a research hotspot in the field. Among the various structures, the one-dimensional (1D) structure has drawn wide attention because of the unique shape anisotropy and spatial confinement effect. Electrospinning technology has become one of the main ways to prepare continuous 1D micro-nano fibers due to the advantages of many types of spinnable materials, low spinning cost, and high controllability of process parameters. This review involves an introduction and a classification of the research progresses achieved in electrospinning technology concerning MA nanofibers from the perspective of compositions, as well as the list of their minimum reflection loss (RL min) and effective absorption bandwidth (EAB). [ABSTRACT FROM AUTHOR]

One-dimensional (1D) ZnFe 2 O 4 @SiO 2 (ZS) nanochains were prepared with Stöber method under external magnetic field. Then, 1D ZS nanochains were covered with a uniform polydopamine (PDA) shell, and the pyrolysis process was completed to obtain 1D ZnFe 2 O 4 @SiO 2 @C (ZSC) nanochains. Finally, 1D flower-like ZnFe 2 O 4 @SiO 2 @C@NiCo 2 O 4 (ZSCNC) nanochains were fabricated through a simple hydrothermal method. The carbon layer with strong dielectric loss enabled the 1D ZSC nanochains to achieve an ultra-wide effective absorption bandwidth (EAB) of 6.22 GHz. Compared with the above nanochains, the 1D ZSCNC nanochains showed more excellent microwave absorption (MA) properties because of the unique 1D flower-like architectures having large surfaces and multiple interfaces. The sample loaded with 30 wt% 1D flower-like ZSCNC nanochains showed strong MA performances with a minimum reflection loss (RL) value of −54.29 dB (11.14 GHz) and an EAB of 5.66 GHz (11.94–17.60 GHz) at the thickness of 2.39 mm. The 1D flower-like ZSCNC nanochains with strong absorption, broad absorption bandwidth (almost the entire Ku band) and thin layer has a good application prospect for the absorption of electromagnetic waves in Ku band. [ABSTRACT FROM AUTHOR]

Thin properties and efficient absorption performance are two significant factors in the practical application of electromagnetic wave absorbers, but still face considerable conflicts. Three-dimensional (3D) Carbon Nanotube (CNTs) interpenetrating network structure has been proved to be an effective strategy to obtain high performance electromagnetic waves (EMW) absorption materials. We report a 3D sea cucumber-like nanomaterial that uses pyrolysis to self-grow CNTs on the surface of bimetallic metal-organic frameworks (MOFs). FeCo bimetallic MOF were successfully prepared and CNTs were grown after the pyrolysis of bimetallic MOF. The excellent EMW absorption performance of FeCo/CNTs composites was attributed to its multiple absorption mechanism. Electromagnetic analysis showed that the 3D structure increases the multiple reflections of the EMW and the CNT produces sufficient polarization effects. The interconnection of CNTs provides more opportunities for electron leap and electron hopping. When the matched thickness is 1.38 mm, the performance of EMW absorption properties showed a minimum reflection loss of − 59.24 dB at 17.10 GHz. Moreover, the ultrathin FeCo/CNTs composites could reach an effective absorption of 10.96 GHz (60.9% of 2–18 GHz) showing an ultra-wide absorption. This work provided options for the modification of MOFs derivatives as excellent candidates for EMW absorbers. • FeCo multi MOF were successfully prepared and self-grown CNTs after pyrolysis. • The 3D structure can extend the transmission path of electromagnetic waves and increase the attenuation effect. • The excellentEMWabsorption performance is mainly attributed to magnetoelectric synergistic effect between FeCo and CNTs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flower-like surface Ni@Co 3 O 4 /RGO composites were designed and fabricated. • The possible microwave absorption mechanism was demonstrated and illustrated. • The optimal reflection loss value of −60.0 dB can be obtained. Novel composite microwave absorption (MA) materials with multiple loss mechanism have attracted considerable attention. In this work, flower-like surface Ni@Co 3 O 4 nanowires were designed and fabricated through chemical reduction method induced by magnetic field, followed by in-situ polymerization, low temperature oil bath and thermal annealing. Then, the Ni@Co 3 O 4 /RGO composites were prepared through a hydrothermal reaction of the Ni@Co 3 O 4 nanowires and graphene oxide suspension. The electromagnetic properties of different loading content samples (15 wt%, 25 wt% and 35 wt%) were measured to investigate the influence of loading content on the MA performance. For the 35 wt% loading sample, the minimum reflection loss (RL min) value of −60.0 dB was determined at the thickness of 2.3 mm, and the maximum effective absorption bandwidth (EAB, RL < −10 dB) of 4.62 GHz can be achieved when the thickness is 1.6 mm. This research provides a reference for exploiting high-efficient flower-like surface magnetic-dielectric composites in the field of MA. [ABSTRACT FROM AUTHOR]

Hierarchical structured ZnFe 2 O 4 @SiO 2 @C@NiO/reduced graphene oxide (ZSCN/RGO) composites were designed and fabricated via a multi-step route. One-dimensional (1D) ZnFe 2 O 4 @SiO 2 nanochains were fabricated through magnetic-field-induced stöber method. ZnFe 2 O 4 @SiO 2 @phenolic resin nanochains were synthesized through in-situ polymerization and then after high-temperature carbonization ZnFe 2 O 4 @SiO 2 @C (ZSC) nanochains were obtained. 1D ZSCN nanochains with flower-like surface were formed after NiO nanosheets grew irregularly on the surface. Finally, ZSCN/RGO composites with ZSCN nanochains anchoring on RGO nanosheets were successfully synthesized. The morphology, structure, composition and magnetic performance were systematically investigated. Moreover, the microwave absorption (MA) properties of ZSCN nanochains and ZSCN/RGO composites were compared. The results indicate that ZSCN/RGO composites exhibit a minimum reflection loss (RLmin) of −66.38 dB (9.58 GHz) and an effective absorption bandwidth (EAB) of 3.44 GHz (8.12–11.56 GHz) at a thickness of 2.45 mm, due to the synergetic effect between ZnFe 2 O 4 , SiO 2 , carbon, NiO and RGO. • One-dimensional ZnFe 2 O 4 @SiO 2 @C nanochains were synthesized successfully. • The flower-like structure was obtained after NiO nanosheets grew on ZnFe 2 O 4 @SiO 2 @C nanochains by the hydrothermal method. • The microwave absorption mechanism of ZnFe 2 O 4 @SiO 2 @C@NiO/reduced graphene oxide was demonstrated in depth. • The strongest absorption of -66.38 dB and the effective absorption bandwidth of 3.44 GHz can be obtained. [ABSTRACT FROM AUTHOR]