Lightweight and mechanically robust carbon aerogel/SnO₂ nanorods composites with heterogeneous structure for electromagnetic interference shielding

Fabricating lightweight and mechanically robust carbon aerogel (CA) for high-performance electromagnetic interference (EMI) shielding is vital yet challenging. In this work, the heterostructure CA/SnO₂ nanorods (NRs) composites are proposed by the fabrication of phenolic-derived CA and followed in-situ growth of nano rod-like SnO₂ via ultrasonic cavitation effect. This strategy introduces countless heterogeneous interfaces in the skeleton while maintaining the original porous conductive skeleton of CA, which can synergistically dissipate and absorb electromagnetic waves. The CA/SnO₂ NRs composites exhibit the EMI shielding effectiveness (SE) of 36.6 dB with a density of 0.33 g cm⁻³, of which the absorbed SE reaches 32.1 dB. Besides, CA/SnO₂ NRs composites also exhibit prominent mechanical properties, flame retardant properties, and outstanding thermal insulation. Such an especial combination of several exceptional properties capacitates the EMI shielding CA/SnO₂ NRs composites to have broad application prospects in fields of aerospace, military, and intelligent electronics.