The exfoliation/dispersion of two-dimensional (2D) materials is of great importance due to their unique properties and applications in electronics as well as energy storage devices. In this paper, we address the challenge of dispersing 2D materials in a scalable and environmentally friendly way. A methodology to efficiently disperse 2D materials [boron nitride (BN) and molybdenum disulfide (MoS2)] in an aqueous solution using a green dispersant, nanofibrillated cellulose (NFC), was introduced. The stable high concentration BN/MoS2 aqueous solutions allow the formation of multifunctional composites and may facilitate roll-to-roll manufacturing. Films and fibers with excellent mechanical strength were fabricated with the BN solution. Additionally, strong and flexible MoS2 films were prepared and used as anodes for sodium ion batteries, indicating flexible battery applications.