Towards Optimized Charge Transport in Multilayer Reduced Graphene Oxides

TL;DR

This paper investigates charge transport in multilayer reduced graphene oxides using multiscale simulations, revealing how interlayer interactions and film thickness influence electrical conductivity, and compares findings with experimental data to guide material optimization.

Contribution

It introduces a multiscale computational approach to understand charge conduction in multilayer rGO, clarifying the role of interlayer interactions and film thickness effects.

Findings

Diffusion worsens with increasing film thickness.

Interlayer hopping dominates conduction when mean free path is short.

Predictions align with experimental data, guiding material optimization.

Abstract

In the context of graphene-based composite applications, a complete understanding of charge conduction in multilayer reduced graphene oxides (rGO) is highly desirable. However, these rGO compounds are characterized by multiple and different sources of disorder depending on the chemical method used for their synthesis. Most importantly the precise role of interlayer interaction in promoting or jeopardizing electronic flow remains unclear. Here, thanks to the development of a multiscale computational approach combining first-principles calculations with large scale transport simulations, the transport scaling laws in multilayer rGO are unraveled, explaining why diffusion worsens with increasing film thickness. In contrast, contacted films are found to exhibit an opposite trend when the mean free path becomes shorter than the channel length, since conduction becomes predominantly driven by interlayer hopping. These predictions are favourably compared with experimental data and open a road towards the optimization of graphene-based composites with improved electrical conduction.