Enhanced Electrical Conductivity of Cellulose Nanofiber/Graphene Composite Paper with a Sandwich Structure

Abstract

A novel conductive paper based on cellulose nanofiber (CNF) and reduced graphene oxide (RGO) with a sandwich structure was successfully prepared through step-by-step vacuum filtration followed by a chemical reduction process in which a CNF layer is sandwiched between two thin RGO layers. This unique design strategy not only provides a highly conductive network for its surface but also maintains the structural integrity of CNF. The sandwich-structured paper exhibits a significantly conductive anisotropy, and the in-plane electrical conductivity is drastically enhanced as 4382 S m–1 with only 4 wt % RGO, whereas it is insulating along the cross-plane direction. This can be attributed to the RGO layers at the top and bottom surface connected in parallel. This high electrical conductivity is greatly superior to most of the cellulose/graphene composite papers obtained by conventional blending processes. Compared with the similar layer-by-layer assembly technique, the present method is more feasible and time saving. Moreover, the sandwich-structured paper shows excellent mechanical strength and good flexibility, which may facilitate its applications in future flexible electronics.

Preparation of conductive cellulose paper through electrochemical exfoliation of graphite: The role of anionic surfactant ionic liquids as exfoliating and stabilizing agents

“…Furthermore, these economical and efficient SAILs alone may find applications as both exfoliating agents and dispersants for other layered or two dimensional materials such as metal dichalcogenides and metal-organic frameworks (Mas-Balleste, Gomez-Navarro, Gomez-Herrero, & Zamora, 2011). This graphene conductive cellulose paper produced here may also find applications in electronic devices as flexible supercapacitors, electrodes, or sensors (Hou, Xu, & Li, 2018;Weng et al, 2011).…”

3D Printing of UV-Curable Polyurethane Incorporated with Surface-Grafted Nanocellulose

“…The disordered and unwrinkled structure was attributed to the non-removal of oxygen atoms and a high degree of exfoliation during oxidation [27]. The micrograph of CNF/PEG shown in Figure 1c presents the dispersibility of CNF with the PEG, while the trace of CNF under a thin layer of rGO was visibly present in Figure 1d [28]. Moreover, the modified CNF shows both the stability of interfacial agents and remains as individual fibrils.…”

A review on graphene based transition metal oxide composites and its application towards supercapacitor electrodes

“…All such 3D graphene-based substances are made of micro-meso and macro-connected pores, huge surface regions and high rate of ion/electron transport channel. To improve efficiency these factors are essential for research into high power and energy as well as overall super-capacity improvements [186,187]. Around most of these 3D graphene buildings showed outstanding electrochemical behavior for energy storage and other functional properties such as physical and catalytic [188].…”