Hierarchical Building Blocks with Alternating Hard Cores and Flexible Chains for Ultrahigh Strength Aerogel

Low strength is a critical issue hindering the development and application of SiO2 aerogels. Although some progress has been made in optimizing mechanical flexibility, there is still a gap from practical application standards. Regarding this, we implemented a molecular-level design featuring an alternating hard-core and soft-chain structure to sacrificially enhance compressive strength and significantly improve deformability, and engineered hierarchical building blocks to bolster structural stability at the nanoscale. The resulting SiO2-based aerogel demonstrated a strong combination of singular performance advantages and multifunctionality, including ultrahigh compressive strength, exceptional deformability and structural stability, thermal superinsulation capabilities, superhydrophobicity, and notable hydrophobic stability. Particularly, the compressive strength not only surpassed previously reported aerogel materials (65.6 MPa at 0.245 g/cm3), but its lightweight high-strength characteristics also outperformed various ultralight 1D nanofiber aerogels (ln(E) ≈ ln(ρ)1.65256). This combination offers an attractive material system for robust thermal superinsulation in mechanically complex and highly humid environments.