Developing microwave absorption (MA) materials with ultrahigh efficiency and facile preparation method remains a challenge. Herein, a superior 1D@2D@1D hierarchical structure integrated with multi‐heterointerfaces via self‐assembly and an autocatalytic pyrolysis is designed to fully unlock the microwave attenuation potential of materials, realizing ultra‐efficient MA performance. By precisely regulating the morphology of the metal organic framework precursor toward improved impedance matching and intelligently integrating multi‐heterointerfaces to boosted dielectric polarization, the specific return loss value of composites can be effectively tuned and optimized to −1002 dB at a very thin thickness of 1.8 mm. These encouraging achievements shed fresh insights into the precise design of ultra‐efficient MA materials.

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The insulating nature of sulfur/Li2S and heavy shuttle effect of lithium polysulfides (LiPSs) hinder the commercialization of lithium–sulfur (Li–S) batteries. To address such issues, we designed and synthesized a porous carambola-like N,S-doped carbon framework embedded with Mo2C particles (designed as N,S–Mo2C/C-ACF) as the interlayer material to block the polysulfide shuttle and it behaves as a catalytic mediator for LiPS conversion. The modified separator of polypropylene functionalized by N,S–Mo2C/C-ACF, showing ultrafast wetting ability to the electrolyte and high lithium ion (Li+) conductivity, proves to be highly effective for inhibiting the polysulfide shuttle and simultaneously promoting the reutilization of adsorbed LiPSs. When used in Li–S batteries by coupling with a Super P/sulfur cathode, over a wide temperature range of 5–55 °C, the as-fabricated batteries delivered excellent rate capability and long cycle stability. Especially, at a high rate of 5 C, the discharge capacities of 405, 630, and 670 mA h gs –1 were achieved when tested at 5, 30, and 55 °C, respectively. The remarkable wide temperature performance is appealing for extended practical application of Li–S batteries.

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Strengthening and functioning effects of Fe 3 O 4 nanowires (Fe 3 O 4 NWs)-reduced graphene oxide (FeNWs-rGO) hybrid on gas barrier, microwave absorption, and electromagnetic interference (EMI) shielding performance of epoxy (EP) composites were systematically evaluated. FeNWs-rGO hybrid was successfully prepared through dopamine (DA) derived onepot coprecipitation, associated with the synchronous surface reduction on GO. The in situ growth mechanism of Fe 3 O 4 NWs on rGO sheets was properly discussed, in which the DA/Fe 3+ /Fe 2+ molar ratio and pH value in the reaction solution were found to be the determining factors in obtaining high quality FeNWs-rGO with a large amount and long length of Fe 3 O 4 NWs. The magnetism feature of FeNWs-rGO endowed the possibility of controlling their distribution state in EP matrix under the action of external magnetic field. The oxygen transmission and moisture diffusion coefficients of EP composites with magnetically aligned FeNWs-rGO at the intensity of 35 mT were clearly reduced as much as 33.6% and 68.0% compared with those of EP composites with randomly distributed FeNWs-rGO, respectively. More importantly, EP composites with different FeNWs-rGO distributions exhibited obvious anisotropy in microwave absorption and EMI shielding performance. Specifically, when FeNWs-rGO was aligned vertical to the direction of incident wave, the remarkable microwave absorption and EMI shielding capabilities of EP composites were achieved at only 2.0 wt % loading content of FeNWs-rGO, mainly due to strong interfacial polarization effect induced by plentiful heterointerfaces and strengthened multiple reflections inside FeNWs-rGO sheets by maximizing their interaction area with the incident wave.

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