Bionic composite nanofibrous aerogel inspired by blind shrimp for broad temperature range thermal insulation and broad frequency range noise reduction

Abstract

There is an urgent need for integrated thermal insulation and noise reduction applications in both military and civilian fields, and nanofibrous aerogel materials with good compression and recovery properties are ideal choices to address this issue. An all-ceramic SiO₂ nanofibrous aerogel (AC-SNFAs) with a bionic blind bristle structure was constructed by the strategy of agarose gel-assisted directional freeze-drying. AC-SNFAs exhibit low thermal conductivity of 0.0232–0.0643 W·m⁻¹·k⁻¹ over the temperature range of −50–800 °C and maintain good structural stability between − 196–1100 °C. The absorption coefficient of the 30 mm sample is greater than 0.8 above 1100 Hz, with an average sound transmission loss (STL) of 33.46 dB. This provides insight into the design of next generation integrated thermal and acoustic insulation materials.