Flexible and ultrathin Fe3O4/Wood/Cu composite films for efficient electromagnetic interference shielding

The issues of electromagnetic wave pollution and electromagnetic interference (EMI) are becoming worse due to the quick growth of wireless communication and the enormous desire for portable, intelligent devices. The development of materials with strong electromagnetic shielding capability and ultra-thin flexibility is urgently needed. The goal of this study was to develop and create a flexible, ultra-thin FeO/Wood/Cu composite film with high EMI shielding performance using in-situ impregnation of FeO and electroless Cu method, followed by densification. The FeO/Wood/Cu-40 composite film exhibits good EMI shielding performance of 56.62 dB and strong conductivity of 188.7 S cm at just 150 μm in thickness. Notably, the FeO/Wood/Cu-40 composite film's specific electromagnetic shielding effectiveness (SSE/t) in the X-band is 4919.60 dB cm g, which is higher than the majority of the hardwood electromagnetic shielding materials that have been reported to date. Because FeO and metal copper provide wood its electromagnetic double loss properties, the FeO/Wood/Cu-40 composite film has a high absorption coefficient (A=0.54), suggesting effective electromagnetic wave absorption. Furthermore, the FeO/Wood/Cu composite sheet has outstanding mechanical qualities and a smooth surface. The developed flexible ultrathin FeO/Wood/Cu composite material may be used for wearing smart devices and has a wide range of potential applications in the area of electromagnetic shielding.