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DOE OSTI · 2499278

Tailoring Nanoporous Silica and Natural Straw Structural Insulation Composites

Abstract

Nanoporous silica exhibits ultralow thermal conductivity as a result of its nanoscale pore size, high pore volume, and specific surface area. In this study, we report the self-assembled surfactant-templated synthesis of nanoporous silica, which is integrated with cellulose fibers derived from natural straw to manufacture high thermal insulation and mechanically robust nanocomposites. The nanocomposite shows a low thermal conductivity of 22.5 mW/(m·K), a compressive modulus of 0.93 MPa, and a hydrophobicity with a water contact angle of 125°. Moreover, we observed a marked reduction in water absorption capacity and a carbon footprint of 0.21 kg CO 2 equiv/kg. Here, this study provides a pathway toward the development of nanoporous structural insulation materials for energy-efficient building applications.

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Zhu, Long, Huang, Yulong, Armstrong, Jason, Ren, Shenqiang. 2024-07-17. Tailoring Nanoporous Silica and Natural Straw Structural Insulation Composites. https://doi.org/10.1021/acsaenm.4c00338

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36 MATERIALS SCIENCE↗