Block Building Architecture for a Multifunctional Broadband Electromagnetic Wave Absorber Based on the Freestanding Resistive Film

As the critical component in the electromagnetic (EM)wave shieldingand stealth technology, using broadband EM wave absorbers in harshenvironments is still challenging in practical applications. In thisletter, a novel way of realizing the broadband absorbers with a blockbuilding method is proposed to broaden their absorptivity to differentapplication scenarios. In particular, the synthesis of the self-supportedcarbon nanotube-cellulose nanocrystal (CNT-CNC) film,which acts as a resistive layer, is independent of selecting substratesduring fabrication and assembling. Therefore, replacing the substratesto meet different application requirements is easy. We experimentallydemonstrate the application of a block building method in realizinga high temperature-resistant and self-repairing EM wave absorber bycombining the CNT-CNC film with ceramics and supramolecularthermoplastic urethane substrates, respectively. Moreover, the CNT-CNCfilm is compatible with laser etching and further offers a convenientway of tuning the absorption frequency after incorporating frequency-selectivesurface design. The proposed block building method offers insightsinto designing multifunctional absorbers.

Automated summary

This letter proposes a novel way of realizing broadband absorbers with a block building method, which broadens their absorptivity to different application scenarios. The self-supported carbon nanotube-cellulose nanocrystal (CNT-CNC) film, acting as a resistive layer, can be synthesized independently of selecting substrates, making it easy to replace and meet different application requirements. Experimental demonstration of a high temperature-resistant and self-repairing EM wave absorber incorporating the CNT-CNC film with ceramics and supramolecular thermoplastic urethane substrates shows the effectiveness of the block building method.