Determination of the lateral size and thickness of solution-processed graphene flakes

Li-Shang Lin,R Brydson,Zabeada Aslam,Wei Bin-Tay,A.V.K Westwood

doi:10.1088/1742-6596/902/1/012026

Li-Shang Lin, R Brydson + Show 3 more

Open Access

https://doi.org/10.1088/1742-6596/902/1/012026

Copy DOI

Journal: Journal of Physics: Conference Series	Publication Date: Sep 1, 2017
Citations: 5	License type: cc-by

Affiliation: University of Leeds

Abstract

We present a method to determine the lateral size distribution of solution…processed graphene via direct image analysis techniques. Initially transmission electron microscopy (TEM) and optical microscopy (OM) were correlated and used to provide a reliable benchmark. A rapid, automated OM method was then developed to obtain the distribution from thousands of flakes, avoiding statistical uncertainties and providing high accuracy. Dynamic light scattering (DLS) was further employed to develop an in-situ method to derive the number particle size distribution (PSD) for a dispersion, with a deviation lower than 22% in the sub-micron regime. Methods for determining flake thickness are also discussed.

Highlights

Graphene has gained enormous interest since its unique properties and practical isolation were demonstrated under ambient conditions [1]
The lateral dimension distribution was measured via direct imaging using two microscopy techniques (TEM and optical microscopy (OM)) and via a fast, but less direct technique based on Dynamic light scattering (DLS)
Flake thickness was estimated by the Mean Grey Value Ratio (MGVR) method which is based on normalised transmission electron microscopy (TEM) Bright Field image contrast [4]

Summary

Introduction

Graphene has gained enormous interest since its unique properties and practical isolation were demonstrated under ambient conditions [1]. We present a method to determine the lateral size distribution of solution–processed graphene via direct image analysis techniques. Dynamic light scattering (DLS) was further employed to develop an in-situ method to derive the number particle size distribution (PSD) for a dispersion, with a deviation lower than 22% in the sub-micron regime. We demonstrate methodologies to determine the lateral size distribution for solution-processed graphene.

Results

Conclusion