Probing graphene grain boundaries with optical microscopy (original) (raw)

Grain boundaries in graphene, crucial for determining its transport properties and performance, are challenging to observe on a large scale. Utilizing optical microscopy, this study reveals a method to observe these grain boundaries directly on graphene grown on copper foil. By selectively oxidizing the copper beneath the graphene through functionalized defect sites, the imaging technique highlights the relationship between graphene grain size and sheet resistance while offering insights into crack propagation influenced by these grain boundaries. This direct observation approach could be extended to other two-dimensional materials.