Flexible and Transparent Bagasse Aerogels for Thermal Regulation Glazing

The preparation of functional composite aerogels for building envelopes, especially for building glazing as the key climate moderator, has been widely investigated to improve the sustainability of buildings. Unfortunately, the prohibitive costs, mechanical brittleness, and optical opacity limit the current development and application of composite aerogels. Herein, using the controllable extraction of cellulose from bagasse, a low-cost (less than $3 per square foot), flexible (>15% elastic deformation under 0.02 MPa) bagasse aerogel film with high visible-light transparency (>80% transmittance of visible light) and superinsulation (0.0158 W m–1 K–1) was developed. These properties were achieved by constructing a uniform three-dimensional network structure using elastic polysiloxane and a mixture of cellulose nanofibers and cellulose nanocrystals in an equal proportion. This cellulosic aerogel film would have the latent potential of application in highly glazed modern buildings to reduce the energy loss from windows.