Nacre-Inspired Hybrid\nMultilayer Insulation Composites

Superinsulation aerogels are characterized by low tensile\nstrength\nand brittleness due to their high porosity. To address these limitations,\nmultiscale architectural design inspired by nacre can be employed.\nThis materials design approach offers a promising strategy for enhancing\nthe mechanical strength of aerogel thermal insulation. In this study,\nwe present nacre-inspired multilayer cellulose-silica aerogel configurations.\nThe cellulose “brick” network imparts structural strength\nto effectively redistribute energy, while the nanoporous “mortar”\nsilica blocks heat transfer, maintaining insulation and fire retardance.\nThe multilayer composites, with a layering configuration of five cellulose\nlayers with four silica layers (5 + 4) and a cellulose layer thickness\nof 1.42 mm, exhibit a thermal conductivity of 31.3 mW/(m·K),\na flexural modulus of 505 MPa, and an impact strength of 7.33 kJ/m<sup>2</sup>. The hydrophobic composite shows a water contact angle of\n127°, enhanced soundproofing with a 27% noise reduction, and\na carbon footprint of 0.49 kgCO<sub>2</sub>eq/kg. The multilayer cellulose-silica\naerogel design provides a robust, eco-friendly thermal insulation\nsolution for green building applications.