This grant provides funding for characterizing and manipulating the adhesive properties of graphene, a single layer of carbon atoms densely packed into a honeycomb lattice that have been shown to have extraordinary mechanical, optical, thermal and electronic properties. Adhesion dictates graphene morphology on surrounding materials, which is in turn closely tied to the electronic and mechanical properties of the graphene. However, the adhesive properties of graphene are largely unexplored, partly because the traditional metrologies of adhesion become unsuitable when dealing with samples of extremely small dimensions. This project bypasses previous limitations by extracting adhesive properties directly from the morphology of graphene placed on patterned substrate surfaces and nano-scale scaffolds. A metrology will be developed to measure the adhesion between graphene and a wide-range of materials, particularly using morphological changes on non-flat substrates. The material, morphological, and environmental factors that influence graphene adhesion to surfaces will be determined. Methods will be developed to manipulate the mechanical properties of graphene using surface structures. Results will be achieved through a research framework that integrates experiments (e.g., atomic force microscopy, electronic transport, Raman spectroscopy) and theory (e.g., multi-scale theoretical and numerical modeling).
There is currently great interest in exploring applications for graphene in next-generation electronics and advanced composite materials. Adhesion plays a pivotal role in the interplay between graphene and other materials, so is a key to the success of future graphene devices and applications. If successful, this project will contribute to an understanding of the interplay between graphene adhesion and morphology which could also have implications for other graphene properties. The energetic framework and experimental protocols developed in this project can be readily adapted to other ultrathin films, and thus have the potential to impact metrology techniques for a wide range of other functional materials.