Nanocrystalline Cellulose-Functionalized Reduced Graphene Oxide Nanosheets and Their Composite Papers

Aqueous-dispersed nanocrystalline cellulose functionalized-reduced graphene oxide (NCC-RGO) nanosheets (the precursor of the composite papers) were prepared via the reaction of graphene oxide (GO) nanosheets, NCC, and ascorbic acid. In this reaction, stiff rod-like NCC was attached to the surface of GO nanosheets via hydrogen bond interactions, which prevented the agglomeration of the nanosheets as the surface oxygen-containing functional groups were removed by ascorbic acid The NCC-RGO composite papers were fabricated using a flow-induced self-assembly strategy with vacuum filtration. NCC-RGO nanosheets underwent layer-by-layer self-assembly on the filter membrane as water permeated the membrane. The structures as well as the electrical and mechanical properties of the NCC-RGO nanosheets and the NCC-RGO composite papers were investigated. The results revealed that the aqueous dispersions of the NCC-RGO nanosheets exhibited long-term stability, consequently producing well-aligned, robust, electrically conductive NCC-RGO composite papers.