Electrical Transport Properties of Graphene Nanoribbons Produced from Sonicating Graphite in Solution

TL;DR

This study presents a simple solution-based method to produce graphene nanoribbons via sonication, and investigates their electrical properties, revealing that polymer electrolyte gating significantly enhances mobility by screening charged impurities.

Contribution

Developed a one-stage sonication method to produce graphene nanoribbons and characterized their electrical transport properties in different gating configurations.

Findings

Graphene nanoribbons with widths from sub-10 nm to tens of nm were produced.

Mobility increased over tenfold with polymer electrolyte top-gate compared to back-gate.

Charge impurity scattering limits charge transport in these nanoribbons.

Abstract

A simple one-stage solution-based method was developed to produce graphene nanoribbons by sonicating graphite powder in organic solutions with polymer surfactant. The graphene nanoribbons were deposited on silicon substrate, and characterized by Raman spectroscopy and atomic force microscopy. Single-layer and few-layer graphene nanoribbons with a width ranging from sub-10 nm to tens of nm and length ranging from hundreds of nm to 1 {\mu}m were routinely observed. Electrical transport properties of individual graphene nanoribbons were measured in both the back-gate and polymer-electrolyte top-gate configurations. The mobility of the graphene nanoribbons was found to be over an order of magnitude higher when measured in the latter than in the former configuration (without the polymer electrolyte), which can be attributed to the screening of the charged impurities by the counter-ions in the polymer electrolyte. This finding suggests that the charge transport in these solution-produced graphene nanoribbons is largely limited by charged impurity scattering.