Boron nitride-nanosheet enhanced cellulose nanofiber aerogel with excellent thermal management properties

Boron nitride nanosheets (BNNSs) are desirable materials for thermal management applications owing to their excellent thermal conductivity. Such property also related to the increased thermal transfer efficiency per unit mass, which can be improved by constructing three-dimensional (3D) structures. Cellulose nanofibers (CNFs) are often used to prepare 3D skeletons and stabilize the dispersion of inorganic fillers. Therefore, CNF/BNNS aerogels were prepared to disperse BNNS in a 3D network. CNF/BNNS aerogel exhibited a thermal conductivity of 0.57 W m^-1 K^-1, which is an enhancement of 443 % compared to 0.105 W m^-1 K^-1 of CNF aerogel. The surface temperature changes of the aerogels were confirmed a strong thermal management capacity. The BNNSs also resulted in the compressive strength increased from 0.25 MPa (CNF aerogel) to 0.37 MPa (CNF/BNNS aerogel). This study provides an effective strategy for the preparation of cellulose-based nanocomposite aerogels with excellent thermal management properties and mechanical properties.