Tailored nanoporous architecture in flexible polymeric aerogel enabling ultrabroadband PHz (VL)-THz-GHz wireless...

Ultrabroadband electromagnetic wave (EMW) transparent materials across petahertz (PHz; visible light range), terahertz (THz), and gigahertz (GHz) range are crucial for sixth-generation (6G) to XG wireless communication. However, current EMW transparent materials cannot meet the design requirements for ultrabroadband PHz-THz-GHz antenna devices. In this study, we report the design and fabrication of flexible polyimide aerogel (PIA) capable of PHz-THz-GHz transmission based on a hybrid cross-linking strategy: (i) The combination of chemical and physical cross-linking enables the construction of a highly porous topology, yielding an ultralow dielectric constant (D_k ∼ 1.1) and improved impedance matching to minimize EMW interfacial reflection; (ii) coupling the hybrid cross-linking network with supercritical CO₂ (scCO₂) drying produces a uniform nanoporous architecture, effectively suppressing EMW Mie scattering; (iii) hybrid cross-linking strategy integrated with fluoride functional group modification design further reduces multiband EMW absorption across the PHz-THz-GHz range. Meanwhile, these aerogel materials demonstrate outstanding environmental stability and mechanical robustness, enabling their use in extended application scenarios. Consequently, an ultrabroadband PHz-GHz antenna was fabricated using the PIA material as the transmission interface, demonstrating continuous wireless communication even when the low-frequency GHz band is partially blocked by maintaining signal transmission through the high-frequency PHz band.