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Zinc borates have merits of low voltage polarization and suitable redox potential, but usually suffer from low rate capability and poor cycling life, as an emerging anode candidate for Na+ storage. Here, a new intercalator‐guided synthesis strategy is reported to simultaneously improve rate capability and stabilize cycling life of N, B co‐doped carbon/zinc borates (CBZG). The strategy relies on a uniform dispersion of precursors and simultaneously stimulated combustion activation and solid‐state reactions capable of scalable preparation. The Na+ storage mechanism of CBZG is studied: 1) ex situ XRD and XPS demonstrate two‐step reaction sequence of Na+ storage: Zn6O(OH)(BO3)3+Na++e−↔3ZnO+Zn3B2O6+NaBO2+0.5H2 ①, Zn3B2O6+6Na++6e−↔3Zn+3Na2O+B2O3 ②; reaction ① is irreversible in ether‐based electrolyte while reversible in ester‐based electrolyte. 2) Electrochemical kinetics reveal that ether‐based electrolyte possesses faster Na+ storage than ester‐based electrolyte. The composite demonstrates an excellent capacity of 437.4 mAh g−1 in a half‐cell, together with application potential in full cells (discharge capacity of 440.1 mAh g−1 and stable cycle performance of 2000 cycles at 5 A g−1). These studies will undoubtedly provide an avenue for developing novel synthetic methods of carbon‐based borates and give new insights into the mechanism of Na+ storage in ether‐based electrolyte for the desirable sodium storage.

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Polystyrene/silicon wrapped ammonium polyphosphate/reduced graphene oxide (PS/SiAPP/rGO) composites with satisfactory flame retardant and electromagnetic interference (EMI) shielding properties were prepared by the approaches of filtration induced assembly and hot‐pressing. The results indicated that the SiAPP and rGO exhibited good dispersivity in the PS matrix. The introduction of the SiAPP and rGO promoted the thermal and fire‐safe performances of PS composites. Moreover, the peak of heat release rate and total heat release of the PS containing 10 wt% SiAPP and 10 wt% rGO were reduced by 47.2% and 30.3%, respectively. Meanwhile, the EMI shielding performance could reach 10 dB. It was proposed that that the SiAPP and rGO promoted the formation of more continuous and compact char residues besides the capture of free radicals, that is, •H and •OH which improved the flame retardant performance of PS. In addition, the multiple reflect and adsorption contributed to enhanced EMI shielding property. Therefore, the assembled PS/SiAPP/rGO system will offer a new approach to broaden the application of PS.

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As a universal polymer material, polystyrene (PS) is widely applied in electrical devices and construction. Thus, it is necessary to improve the flame retardancy and electromagnetic shielding properties of PS material. In this work, PS/silicon-wrapped ammonium polyphosphate/Inorganic acid-treated multi-walled carbon nanotubes composites (PS/SiAPP/aMWCNT, abbreviated as PAC) were prepared via methods of filtration-induced assembly and hot-pressing. Morphology and structure characterization demonstrated that SiAPP and aMWCNT had good dispersion in PS and excellent compatibility with the PS matrix. Thermogravimetric analysis revealed that the addition of aMWCNT to PS improved its thermal stability and carbon-forming characteristics. The peak heat release rate, the peak carbon monoxide production rate, and the peak smoke production rate of the PAC10 composite decreased by 53.7%, 41.9%, and 45.5%, respectively, while its electromagnetic shielding effectiveness reached 12 dB. These enhancements were attributed to the reason that SiAPP and aMWCNT synergistically catalyzed the char generation and SiAPP produced free radical scavengers and numbers of incombustible gases, which could decrease the oxygen concentration and retard the combustion reaction. Therefore, the assembled PS/SiAPP/aMWCNT system provides a new pathway to improve the flame retardant and electromagnetic shielding properties of PS.

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