Knittable, thermally insulating, and sustainable aerogel fibers enabled by ion-mediated hierarchical assembly

Aerogel fibers face intrinsic trade-offs between mechanical robustness and thermal insulation. Here, the authors report ion-mediated, attenuated Coulombic assembly of recyclable heterocyclic aramid nanofibers to programmatically control hierarchical pore structure achieving high tensile strength and ultralow thermal conductivity.