Contact Angle Analysis for the Prediction of Defect States of Graphene Grafted with Functional Groups

Abstract Mass production of graphene is being actively pursued for applications in electronics and energy devices. However, a rapid and simple method to identify the defect states of graphene (which significantly affects the electronic property), prior to the fabrication of the devices, needs to be developed. The manufacturing process requires an easy assessment tool to identify the characteristics of the defects while avoiding cumbersome measurements. This study demonstrates the contact angle analysis to be a plausible assessment tool with the help of molecular dynamics simulations and experiments. The simulations are performed for water droplets on graphene grafted with the most probable functional groups. The contact angle and the shape of the water droplets are interpreted to estimate the type and density of the defects in graphene. This technique can be used as a screening step to identify defective graphene.