Ultrathin alternating multilayered silver nanowire-coated electrospinning films for excellent electromagnetic interference shielding and robust mechanical properties

Developing an ultra-thin flexible polymer film with simultaneously excellent electromagnetic interference (EMI) shielding performance and satisfactory mechanical property is still urgently demanded but challenging for integrated and miniaturized electronics. Herein, alternating multilayered silver nanowire-coating polyvinyl alcohol/ferroferric oxide@silver nanowires (PVA/Fe3O4@AgNW) composite films were successfully fabricated through spraying AgNWs on electrospinning PVA/Fe3O4 films, followed by hot pressing the alternately stacked monolayer PVA/Fe3O4 and PVA/Fe3O4@AgNW films in total of 6 layers. Stemming from superior conductive AgNW networks, alternating multilayered PVA/10-Fe3O4@10-AgNW composite film exhibits the prominent electrical conductivity of 1.5 × 105 S/m. Noteworthily, 6-layered PVA/10-Fe3O4@10-AgNW composite film with a thickness of 30 μm displays excellent EMI shielding effectiveness (SE) of 80.8 dB, on account of the unique alternating multilayered architectures and synergistic effect of conductive AgNWs and magnetic Fe3O4. Furthermore, 6-layered PVA/10-Fe3O4@10-AgNW film possesses satisfactory tensile strength (16.7 MPa) as well as superb flexibility (The fracture strain is 200.6%). This effort sheds a new avenue for ultrathin flexible electrospinning films with both high EMI SE and remarkable flexibility, which has potential application in intelligent, wearable, and portable electronics.