Microwave assisted construction of Ta2CTx MXene/CuInS2 heterostructures toward enhanced dielectric loss and broadband electromagnetic wave absorption

The application of MXene in the electromagnetic wave absorption (EWA) field has been increasingly extensive. To explore the potential of more MXene types, this study has successfully synthesized Ta 2 CT x MXene via HF etching and subsequently prepared a series of Ta 2 CT x MXene/CuInS 2 composites using a microwave-assisted chemical synthesis system. The Ta 2 CT x sample has demonstrated an optimal minimum reflection loss (RL min ) of −27.61 dB with an effective absorption bandwidth (EAB) of 0.8 GHz at a thin thickness of 2.9 mm and a 50 wt% filler loading. In contrast, the Ta 2 CT x MXene/CuInS 2 -50 composite has exhibited a significantly superior EAB of 4.48 GHz at a thinner thickness of 1.5 mm under the same filler loading condition. This enhanced performance has been attributed to the improved impedance matching and increased dielectric loss contributed by the incorporation of CuInS 2 . Furthermore, the multilayered sheet-like structure formed by the two components has established a continuous conductive network, which has effectively dissipated electromagnetic energy through multiple reflections and conductive loss. Ultimately, this work has provided a viable strategy for developing high-efficiency absorbers based on Ta 2 CT x MXene materials.