Silica aerogels are attractive for thermal insulation due to their low thermal conductivity and good heat resistance performance. However, the fabrication of silica aerogels with temperature-invariant superelasticity and ultralow thermal conductivity has remained extremely challenging. Herein, we designed and synthesized a hierarchical cellular structured silica nanofibrous aerogel by using electrospun SiO2 nanofibers and SiO2 nanoparticle aerogels as the matrix and SiO2 sol as the high-temperature nanoglue. This pathway leads to the intrinsically random deposited SNFs to assemble into fibrous cellular structure, and the SNAs are evenly distributed on the fibrous cell wall. The unique hierarchical cellular structure of the ceramic nanofibrous aerogels endows it with integrated performances of the ultralow density of ~0.2 mg cm~(-3), negative Poisson's ratio, ultralow thermal conductivity (23.27 mW m~(-1) K~(-1)), temperature-invariant superelasticity, and editable shapes on a large scale. These favorable multi-features present the aerogels ideal for thermal insulation in the building and construction sector, industrial, and even extreme environment
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