Multi-scale dielectric loss engineering in (Ta2/3Ti1/3)2CTx MXene/sulfide heterostructures for electromagnetic wave attenuation

A novel solid-solution (Ta 2/3 Ti 1/3 ) 2 CT x MXene/CuInS 2 heterostructure was constructed. • Multi-scale dielectric loss engineering was achieved through the synergisy of defects, heterointerfaces, and conductive networks. • The TTC/CS-3 composite delivered a broad EAB of 4.56 GHz at only 1.9 mm. • Interfacial charge redistribution and balanced impedance matching cooperatively enabled efficient EWs attenuation and radar stealth performance. The rational regulation of dielectric loss behavior and impedance matching remains a critical challenge for developing high-performance electromagnetic wave absorbers. Herein, a novel solid-solution (Ta 2/3 Ti 1/3 ) 2 CT x MXene/CuInS 2 (TTC/CS) heterostructure was successfully fabricated through a microwave-assisted solvothermal strategy. Benefiting from the intimate coupling between conductive MXene nanosheets and semiconductive CuInS 2 , a multi-scale dielectric loss engineering platform was established to simultaneously optimize electromagnetic attenuation capability and impedance matching characteristics. Structural analyses demonstrate the successful formation of abundant TTC/CS heterointerfaces accompanied by significant interfacial charge redistribution. The synergistic effects originating from intrinsic vacancies, surface functional groups, multi-cation configurations, and heterojunction interfaces generate abundant polarization centers and multiple dielectric relaxation processes. Meanwhile, the interconnected layered architecture promotes charge transport, conduction loss, and multiple reflections/scattering of incident electromagnetic waves. As a result, the optimized TTC/CS-3 composite exhibits superior electromagnetic wave absorption performance, delivering a broad effective absorption bandwidth (EAB) of 4.56 GHz at a thickness of only 1.9 mm. Electromagnetic parameter analysis reveals that the outstanding performance originates from the cooperative optimization of attenuation capability and impedance matching. Furthermore, radar cross-section simulations demonstrate significantly suppressed electromagnetic scattering behavior for the optimized composite. This work provides an effective strategy for constructing MXene-based heterostructures through multi-scale dielectric configuration and offers new insights into the design of lightweight, broadband, and highly efficient electromagnetic protection materials. A novel (Ta 2/3 Ti 1/3 ) 2 CT x MXene/CuInS 2 heterostructure was constructed for efficient electromagnetic wave dissipation. The synergistic integration of intrinsic defects, heterointerfaces, and interconnected conductive networks enabled multi-scale dielectric loss engineering, promoting interfacial polarization, charge transport, and multiple scattering. Download: Download high-res image (286KB) Download: Download full-size image