Construction of heterogeneous interfaces with SiC-loaded cotton linters-based carbon aerogels: Enhancing broadband...

The high-value valorization of agricultural waste biomass into functional carbon-based materials offers a sustainable pathway to develop lightweight, high-efficiency electromagnetic wave (EMW) absorbing materials. In this work, silicon carbide/carbon aerogel (SiC/CA) composites were fabricated using cellulose-rich cotton linters, a locally generated solid waste in Xinjiang, as the carbon source. Systematic studies indicated that the carbonization temperature significantly influences EMW absorption performance: at 800 °C, a 2.5 mm thick SiC/CA-800 material exhibits a minimum reflection loss (RL_min) of - 49.03 dB, with its effective absorption bandwidth (EAB) extending up to 5.19 GHz. Radar cross-section (RCS) simulations demonstrated that the RCS values of SiC/CA-800 were effectively reduced, with a maximum decrease of - 24.59 dBm², confirming its excellent practical radar dissipation capability. The excellent EMW absorption characteristics can be attributed to conductive losses, dipole polarization, and interfacial polarization arising from multiple heterogeneous interfaces present within the composite material. The study demonstrates that waste cotton linters can be effectively converted into SiC/CA composites with competitive EMW absorption performance, providing a valuable reference for the development of low-cost, biomass-derived EMW absorbing materials.