Application of Nanocellulose/Graphene Oxide Composites in Supercapacitors

Abstract

Graphene is an ideal electrode material for supercapacitors, yet its electrochemical performance is severely impaired by interlayer stacking and aggregation. To address this issue, nanocellulose (NC) extracted from corn stalks was used as a spacer to construct nanocellulose/graphene oxide (GO) composites, thus inhibiting the restacking of graphene sheets. A one-step hydrothermal method was adopted for the composite preparation: NC derived from pretreated corn stalks was mixed with GO solution, and the hydrothermal reactions were conducted at 180 °Ｃ, 200 °Ｃ and 220 °Ｃ, respectively. The as-prepared composites were characterized by SEM, TEM, XRD, XPS, Raman spectroscopy and nitrogen adsorption-desorption measurements, and their electrochemical performances were systematically investigated. The results show that hydrothermal temperature exerts a decisive effect on the microstructural properties of the composites, with the sample prepared at 200 °C exhibiting good comprehensive performance within the tested range. Characterization results confirm the formation of a continuous porous 3D network structure in the composite, where NC effectively hinders the interlayer stacking of GO. Electrochemical tests demonstrate that the GO-NC-200 composite possesses good specific capacitance and excellent charge transfer capability, delivering an areal capacitance of 6.80 F/cm2 and a gravimetric capacitance of 311.74 F/g at a current density of 0.1 A/cm2.