NiCo2O4 nanoneedles decorated woven carbon fibres for electromagnetic shielding in X-band

Nickel cobaltite (NiCo2O4) nanoneedles were grafted in-situ on the woven carbon fibres (WCF) with hydrothermal reaction time increasing from 6 to 18 hr. Shielding effectiveness (SE), measured in the X-band of 12 hr treated NiCo2O4@WCF [72 dB], is considerably larger than the bare WCF [40 dB], with the dominant contribution from absorption. The significant improvement of SE in NiCo2O4@WCF is attributed to an anomalously large dielectric constant (similar to 300-600, over a range of 8.2 to 12.4 GHz) resulting from interfacial polarization between NiCo2O4 nanoneedles and WCF. A technique useful for large-scale production of low density, flexible and thin (similar to 0.4 mm) NiCo2O4@WCF composite fabrics, with excellent absorption of X-band waves, is developed. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The in-situ grafting of nickel cobaltite nanoneedles on carbon fibers significantly improves shielding effectiveness, with absorption being the dominant factor. This technique can be used for large-scale production of flexible and thin composite fabrics with excellent X-band wave absorption capabilities.