CAREER: Fabricating Free-Standing Three-Dimensional Graphene Nanostructures through Functionalization, Folding, and Self-Assembly

This Faculty Early Career Development (CAREER) grant will build a methodology for the fabrication of free-standing, three-dimensional (3D), functionalized, graphene structures. 3D graphene structures have been of great interest in the last few years because of their unique properties and behaviors, which are different from two-dimensional (2D) graphene nanosheets. 3D graphene structures can lead to applications in optics, electronics, optoelectronics, and biomedical devices, which cannot be realized with 2D graphene structures. One of the useful characteristics of graphene-based materials is tunability of their physical and chemical properties through functionalization. Currently, functionalization of 3D graphene-based materials does not exist, because conventional lithographic techniques such as electron beam lithography, photolithography, and nanoimprint lithography are 2D methods which allow patterning and functionalizing only on planar substrates. This research plan seeks to develop nanomanufacturing processes and demonstrate that 3D polyhedral graphene structures can be realized with individually functionalized graphene nanosheets on each face of the 3D structures. The impact of the proposed work is the discovery of knowledge that can be harnessed in developing next-generation 3D nanoelectronics, 3D multi-channel filtering devices, and nanomedical sensors beneficial to human health.

The goal of this award is to demonstrate the unique properties of 3D graphene materials not observed in 2D graphene nanosheets. The heterogeneous 3D functionalization will be accomplished through doping and surface patterning on the 3D structures, which will alter the physical and chemical properties of the 3D nanostructures, leading to a new generation of 3D devices. The specific research interests and CAREER objectives encompass the following: (a) develop a self-assembly and folding processes to transform 2D structures into 3D devices, overcoming the limitations of the conventional lithographic processes and allowing for the creation of free-standing 3D graphene-based (graphene and graphene oxide) polyhedral and nanotube arrays; (b) realize heterogeneous functionalization on the 3D graphene structures, with each graphene-based membrane defining each face of the 3D polyhedron structure and functionalized for specific functionalities; (c) apply the self-assembly process in the development of 3D graphene-based sensors and devices. This work will contribute to solving major problems with using 2D materials and bring significant advances in the development of next-generation nano-enabled devices.