A combination of high-pressure compression molding plus salt-leaching was first proposed to prepare porous graphene/polystyrene composites. The specific shielding effectiveness of the lightweight composite was as high as 64.4 dB cm3 g−1, the highest value ever reported for polymer based EMI shielding materials at such a low thickness (2.5 mm).
23 January 2020 in ACS Applied Materials & Interfaces
An ultra-light and highly conductive cellulose composite aerogel was fabricated by a simple, efficient and environmentally benign strategy. The scaffold structure was well designed from nanofibrillar networks to nanosheet networks by controlling the concentration of cellulose in the sodium hydroxide/urea solution. The obtained conductive aerogel was first reported as an electromagnetic interference shielding material; it exhibits an electromagnetic interference (EMI) shielding effectiveness of ∼20.8 dB and a corresponding specific EMI shielding effectiveness as high as ∼219 dB cm3 g−1 with microwave absorption as the dominant EMI shielding mechanism in the microwave frequency range of 8.2–12.4 GHz at a density of as low as 0.095 g cm−3. This result demonstrates that this type of green conductive aerogel has the potential to be used as lightweight shielding material against electromagnetic radiation, especially for aircraft and spacecraft applications.