Biodegradable PLA/CNTs/Ti3C2Tx MXene nanocomposites for efficient electromagnetic interference shielding

Environment friendly electromagnetic interference (EMI) shielding materials with excellent EMI-shielding efficiency (SE) are urgently required to deal with the increasing electromagnetic wave and environmental pollution. In this work, biodegradable poly(lactic acid) (PLA)/carbon nanotubes (CNTs)/Ti3C2Tx MXene nanocomposites are prepared via co-coagulation and compression molding techniques. The distribution state of Ti3C2Tx MXene or CNTs, the excellent conductivity and EMI-shielding properties of the nanocomposites are confirmed by scanning electron microscopy (SEM), four-probe conductivity tester and vector network analyzer, respectively. The PLA/CNTs/Ti3C2Tx nanocomposites show efficient EMI SE of 24.4 dB for 7 wt% CNTs/8 wt% Ti3C2Tx at the thickness of 0.5 mm. By increasing the thickness of the film, the EMI SE of PLA/CNTs/Ti3C2Tx nanocomposites can be increased to 39.6 dB at 1.9 mm, nearly 99.989% of electromagnetic wave is shielded. The EM wave reflection is the main shielding mechanism of the PLA/CNTs/Ti3C2Tx nanocomposites. Considering future environmental issues, this work provides a novel way for fabricating MXene-based biodegradable EMI shielding materials.