Facile preparation of superior compressibility and hydrophobic reduced graphene oxide@cellulose nanocrystals/EPDM composites for highly efficient oil/organic solvent adsorption and enhanced electromagnetic interference shielding

Abstract

Design of graphene composite aerogel with intriguing attributes usually complicates the preparation process. It is still challenging to achieve high-performance graphene aerogel in a feasible way. Herein, reduced graphene oxide@cellulose nanocrystals aerogel (rGCA)/ethylene-propylene-diene monomer (EPDM) composites (rGCA/EPDM) with well-ordered lamellar porous structure and interconnected networks were prepared through a facile strategy of chemical reduction and self-assembly under natural drying condition. Interfacial bonding formed in the composite aerogel, and cellulose nanocrystals (CNCs) acted as reinforcing skeleton and EPDM chains provided crosslinking elastic network in the composite aerogel, which endowed rGCA/EPDM with superior compressibility and recoverability (up to 90 % strain), excellent mechanical flexibility, enhanced EMI SE (24.1 dB) in the X band of 8.2–12.4 GHz and effective adsorption performance for oil/water separation. The hydrophobic rGCA/EPDM could adsorb various oils and organic solvents from water phase, meanwhile the adsorbed solvents could be recovered by continuous adsorption–desorption process and the adsorption capacity only slightly reduced after 10 adsorption-squeezing or adsorption-volatilization cycles, revealing the good structural stability and recyclable adsorption performance due to its hydrophobicity and robust hierarchical porous structure. Moreover, the composite aerogel could realize real-time adsorption of organic solvent from water surface by pumping force. Such an effective strategy obtaining the composite aerogel exhibits a promising potential in oil cleanup and pollution remediation field.