Exploring excellent dispersion of graphene nanosheets in three-dimensional bacterial cellulose for ultra-strong nanocomposite hydrogels

Homogeneous dispersion of graphene nanosheets in polymer matrices is still a big challenge in the area of nanocomposites. Herein we demonstrate a layer-by-layer (LBL) interface culture strategy to homogeneously distribute graphene (GE) nanosheets in three-dimensional (3D) bacterial cellulose (BC) matrix. In GE/BC nanocomposite hydrogels, the graphene nanosheets are closely bundled by BC nanofibers, which greatly improves the mechanical properties of GE/BC hydrogels. The improvements in tensile strength and modulus over bare BC reach 91% and 279%, respectively, for the GE/BC nanocomposite with 0.30 wt% graphene, which are very impressive for graphene-reinforced hydrogels. The scalable, versatile, and ecofriendly methodology is extendable to the fabrication of other BC-based nanocomposite hydrogels.