MXene-xanthan nanocomposite films with layered microstructure for electromagnetic interference shielding and Joule heating

Abstract

Nowadays, MXenes have attracted significant attention owing to their extraordinary chemical and physical properties. However, it remains challenge to keep their outstanding properties in polymeric composites. Herein, by mimicking nacre with their unique layered brick-and-mortar microstructures, MXene-based nanocomposite films are developed with biocompatible polymer, xanthan. The free-standing nanocomposite films exhibit high electrical conductivity with high tensile strength (11,530 ± 176 S m−1 and 116.48 ± 6.43 MPa for the film with 67 wt% of MXene). Equally importantly, failure strain and toughness of the film with 50 wt% of MXene are dramatically increased to 6.4 and 12.7 times greater than those of neat MXene film. The substantially improved mechanical properties and high electrical conductivity of the nanocomposite films arise from the synergistic by marrying bioinspired layered brick-and-mortar structures with extraordinary material properties of MXene and the best feature of xanthan. The highly electrically conductive and mechanically robust MXene-xanthan composite films were further investigated for electromagnetic interference (EMI) shielding and Joule heating capabilities. It was demonstrated that the nanocomposite films can exhibit the exceptionally high absolute shielding effectiveness (SSE/t = 24,464.8 and 14,490.1 dB cm2 g−1 respectively for the films with 80 wt% and 67 wt% of MXene) and also uniform temperature distribution with high energy transduction efficiency and high thermal stability for Joule heating performance. Therefore, the nacre-inspired MXene-xanthan nanocomposite films can show the great promise for the use in a wide range of engineering applications such as electronics or biomedical devices. This is particularly true when it requires multiple functions including EMI shielding, thermal management, and mechanical robustness.