Environmentally friendly a multifunctional cellulose-based carbon foam for superior electromagnetic wave absorption performance

Ingenious microstructure and suitable multicomponent are still challenging for designing lightweight, low-cost, and resource-renewable microwave absorption materials. Herein, environmentally friendly cellulose-based three-dimensional (3D) porous carbon foams were successfully prepared by freeze-drying and carbonization process. The pyrolysis process under gradient temperature could give rise to tunable electromagnetic (EM) parameters. The minimum reflection loss of carbon nanotubes/cellulose foam under 700°C is −55.4 dB (2.11 mm) at 9.27 GHz benefiting from the construction of double nano-interfaces so-called unique “1D-1D” combination, which can improve interface polarization and impedance matching. Furthermore, such carbon foam exhibits good thermal insulation and hydrophobicity, guaranteeing the stable and durable EM wave absorption application in the field of resist deformation, water or humid environments, and high-temperature attacks.