High-performance chitin-based carbon aerogels with mesoporous structure for electromagnetic interference shielding

Traditional electromagnetic shielding materials based on reflection were no longer suitable for the current complex environment. Carbon aerogels have emerged as potential materials for achieving exceptional electromagnetic interference shielding effectiveness (EMI SE) and low reflection. However, it is still a challenge to find a simple method to achieve the heteroatom doping of carbon aerogels. In this work, nitrogen (N)-doped carbon aerogels were successfully obtained using pure chitin serving as the carbon precursor. The obtained carbon aerogels had obvious mesoporous structure, which significantly enhanced impedance matching between the material and air, thereby prolonged the transmission path of electromagnetic waves (EMWs). Furthermore, the doping of N introduced defects that acted as polarization centers, further facilitating the dissipation of EMWs. The chitin-derived carbon aerogels exhibited an impressive EMI SE of 34.4 dB at 900 °C, with effective absorption coefficient exceeding 90 %. This self-doping approach offered valuable insights for enhancing EMI SE in materials and presented a novel strategy for the development of biomass-based carbon aerogels with tunable electromagnetic shielding properties.