The use of nanofibrillated cellulose to fabricate a homogeneous and flexible graphene-based electric heating membrane.

Nanofibrillated cellulose (NFC) as a natural macromolecule, binder, dispersant, enhancer, was utilized to facilitate the assembly of graphene sheets, imparting a steady stacked structure by the sheets to the electric heating membrane with flexibility and uniform heating performance. Strong interface bonding formed in the membrane, which combined graphene sheets to be a steady conductive network structure for electric heating. The membrane attained an equilibrium temperature rise to 60°C in 3min under 2000Wm-2, which increased linearly with increasing power density and graphene content. Decreased resistance between two electrodes was caused by electric-heat coupling effect which led to a decrease in the membrane's oxygen-containing groups as conducting electrification. The temperature distributing on membrane surface, and that as bent and distorted to different angles even simultaneously at the electric heating status, were all characterized by infrared thermal imaging to indicate the uniform distribution and well bonding performance between NFC and graphene, as well as the great flexibility in the biomass membrane. This study would further broaden the utilization of the natural nanocellulose-graphene biomass composites.