Alternating MXene/Bacterial Cellulose with Brick-and-Mortar Architectures as the Efficient Electromagnetic Shielding Ultrathin Films

The rapid advancement of information technology has intensified concerns regarding electromagnetic interference (EMI) which can disrupt electronic devices and compromise operational stability. This has stimulated growing interest in multifunctional composite materials that integrate efficient EMI shielding with reliable mechanical performance. In this work, alternating MXene/bacterial cellulose (BC) multilayer films were fabricated by vacuum-assisted sequential filtration to construct a brick-and-mortar architecture. The BC nanofiber network effectively reinforced the ultrathin films, with an optimized sample of 14 μm thickness achieving a tensile strength of 84.5 MPa, an EMI shielding effectiveness of 46.5 dB in the X-band (8.2–12.4 GHz), and a specific shielding effectiveness of 24244 dB cm 2 g –1 . The films also showed anisotropic thermal transport and rapid-response Joule heating behavior. These results indicate that the alternating MXene/BC architecture is a practical strategy for balancing conductivity, mechanical robustness, and thermal-management capability in ultrathin EMI shielding films.