Self-assembly of graphene oxide and cellulose nanocrystals into continuous filament via interfacial nanoparticle complexation

Kaitao Zhang,Lukas Ketterle,Topias Järvinen,Gabriela Simone Lorite,Shu Hong,Henrikki Liimatainen

doi:10.1016/j.matdes.2020.108791

Kaitao Zhang, Lukas Ketterle + Show 4 more

Open Access

https://doi.org/10.1016/j.matdes.2020.108791

Copy DOI

Abstract

The present work demonstrates the spinning of conductive filaments from oppositely charged nano-scale entities, i.e., cationic cellulose nanocrystals (CNC) and anionic graphene oxide (GO), via interfacial nanoparticle complexation. Especially, the role of CNC and GO concentration in filament formation was investigated. Moreover, the chemical structure, morphology and composition of formed CNC/GO composite filaments were further characterized. The positively charged CNC formed firstly a complex film with negatively charged GO flake and then the complexed structures were further assembled into macroscale hybrid filament (diameter about 20 to 50 μm). After chemical reduction of the hybrid filament, conductive filaments with an average tensile strength of 109 ± 8 MPa and electrical conductivity of 3298 ± 167 S/m were obtained. The presented approach provides a new pathway to understand the interaction of GO and nanocellulose, and to design macroscopic, assembled and functionalized architectures of GO and nanocellulose composites.

Highlights

The present work demonstrates the spinning of conductive filaments from oppositely charged nano-scale entities, i.e., cationic cellulose nanocrystals (CNC) and anionic graphene oxide (GO), via interfacial nanoparticle complexation
There is a strong possibility that negatively charged GO could complex with positively charged NC to fabricate NC and GO (NC/GO) filament based on interfacial nanoparticle complexation (INC) method
aminoguanidine hydrochloride (AH)-CNC prepared in deep eutectic solvent (DES) system displayed a similar morphology with 92 ± 31 nm in length and a diameter of 6.6 ± 1.4 nm (Fig. 1b)

Summary

Introduction

The present work demonstrates the spinning of conductive filaments from oppositely charged nano-scale entities, i.e., cationic cellulose nanocrystals (CNC) and anionic graphene oxide (GO), via interfacial nanoparticle complexation. The hydrophilic NC can act as a “spacer” to effectively reduce π-π stacking interactions between the graphene and facilitate the absorption of electrolyte, improving the electrochemical performance of the supercapacitors [36,37,38,39] Most of these reported NC/GO hybrid filaments were prepared by traditional wet-spinning method, in which volatile organic coagulation solvents and repeated washing processes are needed. We reported a mild and green method to fabricate micro-sized fibers from oppositely charged nanoparticles using interfacial nanoparticle complexation (INC) This method was carried out under aqueous conditions at neutral pH and at room temperature based on oppositely charged one-dimensional (1D) CNF and CNC [40,41]. Different from the complexation with soluble polyelectrolytes, the INC complexation reported here is between two non-soluble charged nanomaterials, i.e., two dimensional (2D) GO nanosheets and 1D CNCs, which may broaden the suitable materials for the INC complexation (from 1D with 1D to 1D with 2D)

Methods

Results

Conclusion