A Simple Route towards High-Concentration Surfactant-Free Graphene Dispersions

TL;DR

This paper presents a straightforward solvent exchange technique to produce high-concentration, surfactant-free graphene dispersions, enabling simple fabrication of transparent conductive films with properties comparable to more complex methods.

Contribution

The study introduces a novel, simple solvent exchange process using distillation to achieve high-concentration, surfactant-free graphene dispersions from natural graphite.

Findings

High-concentration graphene dispersions achieved without surfactants

Transparent conductive films with comparable properties to complex methods

Efficient solvent exchange method based on boiling point differences

Abstract

A simple solvent exchange method is introduced to prepare high-concentration and surfactant-free graphene liquid dispersion. Natural graphite flakes are first exfoliated into graphene in dimethylformamide (DMF). DMF is then exchanged by terpineol through distillation, relying on their large difference in boiling points. Graphene can then be concentrated thanks to the volume difference between DMF and terpineol. The concentrated graphene dispersions are used to fabricate transparent conductive thin films, which possess comparable properties to those prepared by more complex methods.