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It is well-known that the absorbing property of materials is related to the microstructure and can be enhanced by magnetic nanoparticles coating. However, the mechanism is still unclear that the magnetic coating structure plays an important role in the microwave absorption behavior. Hence, a novel kind of absorber with efficient performance and relatively clear enhancement mechanism is very necessary. To solve these problems, polyaniline@MoS2 nanowires (PANI@MoS2 NWS) and a series of polyaniline@MoS2@Fe3O4 nanowires (PANI@MoS2@Fe3O4 NWS) with hierarchical structure were successfully prepared by in situ polymerization and versatile hydrothermal reactions and investigated in microwave absorption. The results reveal that compared with the articles related to MoS2-based composites, the as-prepared PANI@MoS2@Fe3O4 NWS (e2) displays the widest absorption frequency range (6.48 GHz) and strong absorption (−49.7 dB at a thickness of 1.3 mm), and the excellent MAP can be interpreted by optimizing impedance matching...

The development of electronic makes increasing attentions focus on the high thermally conductive polymer composites. In this work, outstanding epoxy nanocomposites embedded with 3D structure fillers of silver nanowires@SiO2 and graphite nanoplatelets are prepared successfully. Insulative SiO2 layers coating on the surface of silver nanowires can not only provide abundant silicon hydroxyl groups to react and form strong covalent bonding with epoxy matrix and graphite nanoplatelets, minimizing the scattering of phonon and contributing to construction of thermally conductive network, but also effectively protect electrical insulation from the forming of electrical conductive pathways. An ultrahigh thermal conductivity of nanocomposites 1.092 W/m K, an enhancement of 474% to pristine epoxy, is achieved only with low filler volume fraction of 0.8 vol% silver nanowires@SiO2 and 2.7 vol% graphite nanoplatelets, at the same time, an ultralow volume conductivity less than 1 × 10−5 S/cm is available at the frequency range 1 × 102Hz to 1 × 106Hz, which indicates strong potential in the field of electronic packaging.

An excellent PPy/NiFe2O4/CS microwave absorbing materials with a three-layer core–shell structure, was synthesized successfully by two reaction steps of solvothermal reaction and in situ polymerization. The surface morphology, phase structure and chemical components of the composite have been characterized by a scanning electron microscope, X-ray diffraction and X-ray photoelectron spectroscope. The results suggest that the surface of CS is covered by NiFe2O4 completely and PPy wraps the obtained NiFe2O4/CS successfully. The conductivity and the saturation magnetization (Ms) of the resulting PPy/NiFe2O4/CS composites are 0.38 S/cm and 46 emu/g, respectively. The vector network analysis shows the composite performs better microwave absorbing ability than that of CS and NiFe2O4/CS. The maximum reflection loss of the composite with 1.97 mm coating thickness is −53 dB at 10.5 GHz and the bandwidth of reflection loss less than −10 dB is 3.4 GHz (8.9–12.3 GHz). This ternary composite with light weight, thin thickness and strong absorbing capacity can be an attractive candidate in the field of microwave absorption.