Bacterial cellulose composite aerogel with high elasticity and adjustable wettability for dye absorption and oil–water separation

Recently, cellulose-based biomass aerogel, as a high performance adsorption material, has received considerable attention. However, it remains a huge challenge to prepare cellulose aerogels with outstanding mechanical properties by simple and environmentally-friendly strategies. Here, we describe a green one-pot method to prepare a versatile bacterial cellulose/γ-(2,3-epoxypropoxy) propytrimethoxysilane trimethoxysilane composite aerogel (BK aerogel). The elasticity of BK aerogel is significantly improved and up to 96.4% after compression under 80% strain. Further, the elastic recovery can reach 87.8% over 50 times compressions at a set strain of 80 %, implying the obtained composite aerogel possesses strong fatigue resistance. BK aerogel could be soaked in water to adsorb cationic dyes and reused without being damaged. In addition, the prepared BK aerogel is rich in hydroxyl and epoxy groups, so its surface chemistry can be further adjusted. Taking hydrophobic modification as an example, the prepared aerogel can be used for oil–water separation and reused by mechanical squeezing. This study paves a simple and green solution for developing high elastic cellulose nanofiber aerogel with adjustable surface chemistry to meet diverse applications.