Lightweight and sustainable recycled cellulose based hybrid aerogels with enhanced electromagnetic interference shielding

Developing lightweight, sustainable, high porosity, and high-performance electromagnetic interference (EMI) shielding apparatus is essential to diminish electromagnetic contamination for protecting human health and electronic devices. Herein, 1D carbon nanotubes (CNTs) and 2D graphene nanoplatelets (GNPs) functionalized recycled cellulose aerogel (RCA) were fabricated via a facile method by freeze, solvent exchange, and ambient drying. The effect of nanofiller type and quantity on the structural, morphological, electrical, thermal and EMI shielding performance of the RC-based aerogel were investigated. The as-prepared hybrid aerogel displays the maximum 40.2 dB electromagnetic interference shielding efficiency (SE) at 8.92 dB GHz with absorption dominant characteristic. CNTs:GNPs nanofillers in recycled cellulose matrix provoked conductivity mismatching and increased interfacial polarization loss. At a density of 0.087 gcm-3, CNTs:GNPs; 7:7%wt. doped RCA exhibits a highly specific SE (SSE) value of 461.95 dBcm3g-1 and an absolute SE (SSE/t) value of 2309.29 dBcm2g-1. These results show that the CNTs:GNPs; 7:7%wt. doped RCA can meet practical applications' lightweight and high-efficiency EMI shielding requirements.