Hierarchical assembly of sub-1 nm nanowire for the construction of aerogels

Sub-1 nm nanowires (SNWs) exhibit exceptional physicochemical properties. However, their fabrication into three-dimensional macroscopic materials for practical applications remains a significant challenge. Herein, we report a polarity-induced hierarchical assembly strategy combined with freeze-casting to fabricate silanized SNW aerogels (Si–SNWAs) using GdOOH SNWs as building blocks. Through polarity induction and methyltrimethoxysilane mediation, SNWs hierarchically assemble into micron-scale tertiary fibers, forming continuous 3D porous networks. The resulting Si–SNWAs feature ultralow density, superhydrophobicity, and excellent mechanical flexibility and stability, outperforming unmodified SNWAs in terms of cyclic compression and bending resistance. Furthermore, Si–SNWAs exhibit not only passive thermal management capability but also favorable hydrophobic–oleophilic performance, with an oil adsorption capacity of 19–29 g g⁻¹ and satisfactory reusability. This strategy is also universal for multicomponent rare earth SNW coassembly, offering a flexible route for designing SNW-based aerogel materials.