Recyclable polyvinyl alcohol/silvered carbon fiber composite foam with excellent electromagnetic shielding and mechanical stability

Lightweight, recyclable, and ultra-efficient materials for electromagnetic interference (EMI) shielding have garnered significant interest owing to the rapid advancements in 5G communications. Inorganic fiber-based EMI shielding materials that are both capable of withstanding extreme conditions and recyclable have a significant impact on promoting sustainability and broadening their range of applications. In this work, a lightweight, recyclable porous polyvinyl alcohol (PVA) fiber /silver-plated carbon fiber (CF@Ag) composite foam was fabricated by the foam template method. Due to the excellent electrical conductivity of CF@Ag and the abundant pores within the foam material, electromagnetic waves (EMWs) are significantly attenuated, resulting in electromagnetic interference shielding effectiveness (EMI SE) of 86.1 dB and electromagnetic interference specific shielding efficiency (EMI SSE) of 5100 dB·cm³·g⁻¹. Additionally, the composite foam possesses attributes such as low density, recyclability, efficient Joule heating, rapid electrical response, and temperature-adjustable properties. Given its outstanding properties, the composite foam shows significant potential for practical applications under diverse environmental conditions.