Ultrathin Biomimetic Polymeric Ti₃C₂T _x MXene Composite Films for Electromagnetic Interference Shielding

Lightweight, ultrathin, and flexible electromagnetic interference (EMI) shielding materials with high electromagnetic shielding effectiveness (SE) and excellent mechanical robustness are greatly desired for miniaturized and highly integrated electronics. Herein, for the first time, a freestanding, ultrathin, and flexible Ti₃C₂T _x/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) composite film with a "brick-and-mortar" structure is biomimetically designed and fabricated via a vacuum-assisted filtration process. The ultrathin polymeric composite film with a weight ratio 7:1 of Ti₃C₂T _x to PEDOT:PSS is only 11.1 μm in thickness but exhibits a high EMI SE value of 42.10 dB. Meanwhile, the tensile strength increases considerably from 5.62 to 13.71 MPa and the corresponding ruptured strain increases from 0.18 to 0.29% compared with pure Ti₃C₂T _x MXene film, respectively. Moreover, the hybrid film displays a superior conductivity of 340.5 S/cm and an outstanding specific EMI shielding efficiency of 19 497.8 dB cm² g^-1. The superior electrical conductivity and specific EMI shielding efficiency imply the excellent potential of the Ti₃C₂T _x/PEDOT:PSS composite films for ultrathin, lightweight, and flexible EMI shielding materials.