Bionic octopus structure Inspired Stress-Driven reconfigurable microwave absorption and multifunctional compatibility in infrared stealth and De-icing

[Display omitted] •The bionic octopus structure-inspired C/Fe3C foams are successfully constructed.•The timely switchable microwave absorption is achieved from “off” to “open” mode.•The C/Fe3C foam reveals a broad absorption bandwidth of 7.8 GHz at “open” mode.•It also shows ideal cylitic stability, infrared stealth and de-icing properties. Constructing intelligent materials with self-adjustable microwave absorption, infrared stealth and de-icing performances has been of great importance to make the devices and equipment adapt to the variable electromagnetic environment. However, the concurrent achievement of desired microwave absorption, timely switching and multifunctional compatibility is the key issue to be urgently resolved but still remains an enormous challenge. Inspired by the flexible octopus tentacles biomorph, the bionic structure of carbon foam coated by Fe3C particles (CCF) is synthesized via an in-situ carbothermal reduction. Wherein, the carbon foams serve as the basic octopus tentacle skeleton and the magnetic Fe3C particles act as suckers on the surface, providing both sufficient dielectric and magnetic loss by regulating N-defects elaborately. As a result, the CCF hybrids reveal obviously compressive-sensitive microwave absorption characteristics, accompanied by tremendous variations of permittivity and permeability. Moreover, the excellent cyclic mechanical stability, high thermal management and de-icing properties are also explored, which reveals the great potential for multifunctional applications as smart microwave absorbers in multifunctional fields.