Absorption-dominant EMI shielding performance of multiple folded Bi2Se3/PVDF nanocomposite films

Absorption-dominant electromagnetic interference (EMI) shielding materials are promising in reducing electromagnetic radiation pollution, but their preparation processes are usually difficult and unsuitable for large-scale preparation. In this work, multiple folded Bi₂Se₃/PVDF nanocomposite films were fabricated by using a convenient tape-casting method and multiple folding, which can be easily extended in industrial applications. The EMI shielding effectiveness (SE) of the composite materials was investigated, which shows typical absorption-dominant behavior and can substantially reduce secondary reflections. Specifically, for the 35%(in volume) Bi₂Se₃/PVDF nanocomposite film, the SE_A of single-layered film with a thickness of 60 μm reaches 20 dB while SE_R is lower than 5 dB. After folding the film into eight layers, the SE_A increased to 50 dB while SE_R remains below 5 dB. This method provides an effective way to the fabrication of absorption-dominant electromagnetic absorption (EMA) and EMI shielding material.