MXene/Polylactic Acid Fabric-Based Resonant Cavity for Realizing Simultaneous High-Performance Electromagnetic Interference (EMI) Shielding and Efficient Energy Harvesting

ACS Appl Mater Interfaces. 2022 Mar 30;14(12):14607-14617. doi: 10.1021/acsami.2c01160. Epub 2022 Mar 17.

Abstract

Proliferation in telecommunications and integrated/intelligent devices entails an intense concern for electromagnetic interference (EMI) shielding and versatility. It remains an activated passion to launch infusive EMI shielding materials integrated with self-powered peculiarities. Herein, a double-layered MXene/polylactic acid (PLA) fabric resonance cavity (D-MPF-RC) comprised of two MXene/PLA fabrics (MPFs) with alternating MXene and PLA structures that are separated by a poly(tetrafluoroethylene) (PTFE) frame is developed. The D-MPF-RC achieved 48.5 and 74.8% improvement in SET and SEA, and 24.6% reduction in SER by introducing the double-layered structure and increasing the resonance cavity (RC) distance without varying the material composition and cost. A high shielding efficiency (SE) of 92.3 dB was obtained at an RC distance of 6 mm owing to the synergetic effects of multiple reflections and destructive EM wave interference. The tribopolarity difference between PLA and MXene and the RC structure made the D-MPF-RC a readily available triboelectric nanogenerator (TENG) that could convert mechanical energy into electricity. The D-MPF-RC TENG demonstrated an open-circuit voltage of 88 V and achieved a peak power density of 35.4 mW m-2 on a 6.6 MΩ external resistor, which made it possible to charge capacitors and serve as a self-powered tactile sensor. This report offers new insights into the design of high-performance EMI shielding shields with a resonance cavity and proposes a feasible pathway to integrate them with energy harvesting capabilities.

Keywords: MXene; electromagnetic interference shielding; energy harvesting; resonance cavity; triboelectric nanogenerator.