Fire retardant cellulose aerogel with improved strength and hydrophobic surface by one‐pot method

Bio‐based materials with multifunctional performance are getting immense attention nowadays for their environment friendly and renewable character. Inspired by toughening effect of graphene nanosheets and borate chemistry, a simple in‐situ borate crosslinking in water and freeze‐drying method was employed to fabricate a fire retarded bio‐based aerogel. The structure of the material was evaluated and analysis by SEM, XRD, FTIR, Raman and XPS. Importantly, the bio‐based aerogel has improved strength and adsorption properties due to unique structure. The compressive strength of rGO(reduced graphene oxide) + CMC (carboxymethyl cellulose) aerogel could reach 128 ± 2.1 kPa which is five times that of neat CMC aerogel. The bio‐based aerogel can load more than 2500 times of self‐weight. The adsorption capacity for organic solvents and oil of rGO+CMC aerogel is also greatly improved by a little rGO (1%) introducing due to its unique porous structure and hydrophobic nature of rGO. Additionally, rGO+CMC aerogel is also found fire resistant with relatively low thermal conductivity due to the borate and GO introduction.