Fe₃O₄@PDA-functionalized bacterial cellulose aerogels for oil/water separation

Bacterial cellulose (BC) aerogels provide a renewable biological macromolecular scaffold for constructing functional separation media due to their three dimensional nanofibrous network and abundant hydroxyl groups. In this study, BC derived composite aerogels were developed via a multiscale functional coordination approach, incorporating Fe₃O₄@PDA nanoparticles and silane derived hydrophobic domains into the cellulose framework. The BC macromolecular network preserved the porous architecture and supplied reactive sites for PDA mediated anchoring and silane condensation, while Fe₃O₄@PDA and FAS/MTMS enhanced interfacial adhesion, surface roughness, magnetic recoverability, and water repellency. The resulting composite aerogel exhibited excellent comprehensive performance, such as acid and alkali resistance, thermal stability, and self-cleaning ability. It retained over 80% recovery after 100 compression cycles at 50% strain and displayed outstanding hydrophobic and oleophilic behavior (water contact angle 161.9°) in oil/water separation. The adsorption capacities for oils and organic solvents were ranged from 20.73 to 48.21 g/g with over 85% capacity retention after 50 adsorption/desorption cycles and a continuous separation efficiency of 99.93%.