Flexible multifunctional MXene/polyimide films with Janus structure for superior electromagnetic interference shielding
摘要
Flexible polymer-based films for electromagnetic interference (EMI) shielding are of great importance in wearable devices, sensors, and electronic communications. In this work, after synthesizing water-soluble polyamide acid (PAA), MXene/PAA films with Janus structure are prepared by layered solution casting method, and followed with thermally annealing to obtain MXene/polyimide (PI) films with Janus structure. The unique Janus structure provides MXene/PI films with the unique “conductive on one side and insulating on the other” property. When the MXene content is 50 wt%, the MXene/PI film shows EMI shielding effectiveness (SE) of 57 dB. Moreover, the MXene/PI film also presents outstanding electrothermal and photothermal conversion performances. The MXene/PI film quickly reaches stabilized temperature of 108 °C when the applied voltage is 2 V. Under simulated solar irradiation with the power density of 120 mW/cm2, the surface stabilization temperature is to 87 °C. In addition, the MXene/PI films also show excellent structural stability and flame retardancy.