Macroscale amphiphilic aerogel fibers made from nonwoven nanofibers for large active mass loading

Fiber-shaped templates that can be easily loaded with a large amount of hydrophilic and/or lipophilic active materials in a facile process like dip coating, will find many applications including for wearable electronics. Here, macroscale amphiphilic aerogel-like fiber, made from electrospun glycerol-functionalized polyacrylonitrile (PAN) nanofibers (GPN) on a centering metal wire, is reported. With its high porosity, large void space, and both hydrophilic and lipophilic characteristics, this unique GPN aerogel fiber can absorb a large amount of aqueous and oil solutions dispersed with different active materials. In particular, poly (3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PP) represented water-soluble active material is selected to prepare PP-loaded fiber, which is further coated with polyaniline (PANI). The PP@GPN/Ti and PANI@PP@GPN/Ti fibers are studied as electrodes for flexible yarn-shaped solid-sate supercapacitors. A fiber-length-specific capacitance as large as 243 mF cm⁻¹ is measured at 0.1 mA cm⁻¹, one of the best capacitances ever reported for fiber supercapacitors. Colza oil is also tested as a representative oily solvent to investigate the load capacity of GPN aerogel fiber and a mass loading of 124 μl cm⁻¹ is achieved. These results suggest that our unique amphiphilic aerogel fiber could act as a carrier loading a large amount of active masses for many novel applications.