Liquid Metal-Modified MXene Composite Films for Electromagnetic-Multispectral Compatibility
The proliferation of multispectral detection platforms demands materials that simultaneously satisfy electromagnetic interference (EMI) shielding and infrared (IR) camouflage without compromising radio-frequency (RF) transmission. Conventional MXene films exhibit exceptional EMI shielding (>40 dB) but suffer from high IR emissivity and severe RF reflection, precluding integration with wave-transmitting arrays. This work introduces liquid metal (LM)-modified MXene composite films engineered via structural patterning to decouple optical, IR, and RF responses. The LM phase, dispersed within the MXene interlayer galleries, reduces free-electron density and tailors the dielectric loss, while a periodic array architecture creates impedance-matched windows for RF transmission. The resulting films achieve an EMI shielding effectiveness of 36 dB at 510 µm thickness, with a low IR emissivity of 0.36 and an RF transmittance exceeding 80% in the X-band. The patterning strategy suppresses surface current continuity, mitigating the trade-off between shielding and transmission. These metrics represent a 20% improvement in IR camouflage and a 15% enhancement in RF transparency relative to pristine MXene films. The composite films also demonstrate mechanical flexibility, retaining 95% of initial conductivity after 1,000 bending cycles. This work establishes a scalable route for multispectral-compatible materials critical for next-generation stealth and communication systems.