Ultrathin, Strong, and Highly Flexible Ti₃C₂T MXene/Bacterial Cellulose Composite Films for High-Performance...

The fabrication of ultrathin films that are electrically conductive and mechanically strong for electromagnetic interference (EMI) shielding applications is challenging. Herein, ultrathin, strong, and highly flexible Ti₃C₂T MXene/bacterial cellulose (BC) composite films are fabricated by a scalable in situ biosynthesis method. The Ti₃C₂T MXene nanosheets are uniformly dispersed in the three-dimensional BC network to form a mechanically entangled structure that endows the MXene/BC composite films with excellent mechanical properties (tensile strength of 297.5 MPa at 25.7 wt % Ti₃C₂T) and flexibility. Importantly, a 4 μm thick Ti₃C₂T/BC composite film with 76.9 wt % Ti₃C₂T content demonstrates a specific EMI shielding efficiency of 29141 dB cm² g^-1, which surpasses those of most previously reported MXene-based polymer composites with similar MXene contents and carbon-based polymer composites. Our findings show that the facile, environmentally friendly, and scalable fabrication method is a promising strategy for producing ultrathin, strong, and highly flexible EMI shielding materials such as the freestanding Ti₃C₂T/BC composite films for efficient EMI shielding to address EMI problems of a fast-developing modern society.