MXene/PDMS composite foam with regulatable cell structures for improved EMI shielding performance

Abstract The construction of conductive network and the design of material structure are the key points of polymer‐based shielding materials. Herein, we reported a MXene/PDMS composite foam material with adjustable cell structure and high efficiency electromagnetic interference (EMI) shielding. Few‐layered MXene is used as a conductive filler to construct three‐dimensional conductive networks by in situ chemical etching. Meanwhile, a series of polystyrene microspheres with different sizes were prepared by applying suspension polymerization method as templates to introduce different cell sizes and densities for PDMS‐based materials. The density and EMI shielding performance of composites can be improved by adjusting the cell structure. Compared with the unfoamed MXene/PDMS composites, the composite foam in this work not only reduces the material density greatly but also improves the microwave absorption performance with smaller cell size. This method provides a simple and effective guide for changing material density and absorbing mechanism by introducing cell structure into polymer‐based materials in the future.