Tunable High-Performance Electromagnetic Interference Shielding of VO₂ Nanowires-Based Composite

The unique metal-insulator transition of VO₂ is very suitable for dynamic electromagnetic (EM) regulation materials due to its sharp change in electrical conductivity. Here, we have developed an off/on switchable electromagnetic interference (EMI) shielding composite by interconnecting VO₂ nanowires (NWs) in poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) to form conductive networks, resulting in outstanding performance at the X and Ku bands with maximum change values of 44.8 and 59.4 dB, respectively. The unique insulator-to-metal transition (IMT) of VO₂ NWs has dominated the variation of polarization loss (ϵ_p″) and conductivity loss (ϵ_σ″) for the composites, which is the mechanism of EMI shielding switching between off and on states. Furthermore, the composite exhibits good cycling stability of the off/on switchable EMI shielding performance and has excellent mechanical properties, especially with 200 times abrasion resistance without obvious weight loss. This study provides a unique approach for dynamic switching of EM response with the potential to construct practical intelligent EM response systems for next-generation smart electromagnetic devices in various scenarios.