Multifunctional nanofiber aerogels for environmental applications: Oilwater separation, thermal insulation, fireproofing

The development of multifunctional nanofiber aerogels offers promising solutions for environmental protection but poses significant challenges. In this study, amidoximated polyacrylonitrile and silica nanofibers were synthesized to fabricate multifunctional silica/amidoximated polyacrylonitrile nanofiber aerogels. These aerogels were subjected to a sacrificial template combustion treatment, which resulted in the removal of amidoximated polyacrylonitrile nanofibers and the reorganization of silica nanofibers. The resulting combusted aerogels exhibited ultralight properties with a density of 6.6 mg/cm 3 and a porosity of 99.58 %. They demonstrated excellent elasticity and flexibility, with no significant plastic deformation after 100 compression cycles at 60 % strain. The combusted aerogels achieved an ultra-low thermal conductivity of 0.0317 W/m·K, and exhibited high hydrophobicity with a water contact angle of 145°. These aerogels demonstrated outstanding oil spill adsorption performance, with a capacity of up to 177 g/g for organic solvents. Additionally, the aerogels displayed superior fire-proofing properties, effectively adsorbing flammable materials and preventing fire propagation in the event of fuel leakage or ignition. This work highlights the potential of multifunctional nanofiber aerogels as efficient materials for environmental applications, including oil spill adsorption, thermal insulation, fire-proofing, and oil-water separation, contributing to sustainable and practical solutions for environmental protection.