Biogenic Straw Aerogel Thermal Insulation Materials

Biogenic wheat straw is a carbon‐storing building insulation material. However, the enzymatic hydrolysis ratio of its cellulose is relatively low due to the presence of hemicellulose and lignin hindering its thermal insulation performance. Herein, aerogel and straw composites are reported with thermal conductivity of 35 mW m −1 K −1 , while high‐cellulose fiber conversion in straw is obtained using a hybrid mechanical and chemical process. Furthermore, it is shown that the in situ cellulose‐reinforced silica aerogel nanocomposites exhibit an optimal thermal conductivity of 32 mW m −1 K −1 using 50 wt% of aerogel. Moreover, the hydrophobic aerogel–cellulose composites show a low density, high porosity (90%), high compression modulus (1.9 MPa), superhydrophobicity, and superior reusability. Herein, a cost‐effective and facile method to manufacture biogenic composites from agriculture waste materials, promising for carbon‐sequestration building insulation applications is provided.