Direct evaluation of CVD multilayer graphene elastic properties†
Abstract
The rolling of semiconductor thin films with graphene layers on top is carried out to integrate distinct material classes. Tubular structures obtained can span from the nanometer to the micrometer range, providing controlled and homogeneous curvature on few-layer CVD graphene systems. Scanning electron microscopy measurements reveal an increase in the tube radius for larger amounts of stacked/rolled graphene sheets. The relation between the retrieved radii for different layered configurations and total layer thickness is fitted with continuum elasticity theory, directly providing elastic parameters such as Young modulus and Poisson's ratio for few-layer graphene systems. X-ray diffraction and Raman spectroscopy evidence that surface modifications due to the transferring methods are negligible and that layer-to-layer registry (graphitization) is not observed. The concept of rolling up layered materials for direct evaluation of elastic properties can be extended to other two-dimensional systems.