Highly Conductive Reduced Graphene Oxide Films for High Performance Electronic Devices

Clemson University, Clemson SC

Investigators

Abstract

Graphene has proven to be a truly unique material and the record holder for a number of physical parameters. It is expected that employment of graphene as a highly conductive and transparent material would create a new class of electronic devices characterized by excellent durability and flexural freedom. However, despite recent significant progress in scaling up fabrication of large area graphene sheets the fabrication methods still require significant effort and sophisticated multistage handling of the material. To this end, this award targets the manufacture of highly conductive graphene-based films from micron-scale sheets of reduced-graphene oxide, which can be obtained from naturally occurring graphite. The manufacturing method in this project is environmentally friendly, does not involve toxic organic solvents, and utilizes conventional industrial equipment. The approach has a significant potential to rapidly grow to industrial scale and, therefore, increase the competitiveness of US based-manufacturing and create employment opportunities. In course of the work significant effort will be directed to increase the numbers of students, especially underrepresented minorities and women, who wish to pursue advanced degrees in science and engineering. Students will benefit greatly from this project's interdisciplinary nature and hands-on approach. The ultimate goal of this work is the design and understanding of a robust and scalable nanomanufacturing method for the fabrication of highly conductive, highly flexible, and transparent reduced graphene oxide (rGO) based nano-scale layers or films via a facile dip-coating process assisted with polymer adsorbed layers. The method is based on enveloping individual graphene oxide (GO) sheets in few nm thick polymer layers allowing for near-perfect formation of the GO monolayer by scalable conventional dip-coating. After the dip-coating a polymer interlayer is deposited on the GO/ RMS (reactive macromolecular super-spreader) monolayer by adsorption. The polymer interlayer is employed to promote formation of the second GO monolayer (by dip-coating) and provide carbon atoms to connect the bottom and upper rGO monolayers during the GO reduction. This work directly addresses a number of the grand challenges for the large-scale nanomanufacturing of rGO-based conductive transparent flexible films. Specifically, it is expected that the research manufacturing method will allow the straightforward and reproducible fabrication of tight GO monolayers on non-conductive substrates, control of the thickness of the rGO layer with single layer precision, and achieve high coherency and robustness of the fabricated layer. In terms of properties, the project targets the manufacture of highly conductive (low sheet resistance) and transparent (low absorbance in visible region) rGO-based nanoscale films on non-conductive oxide surfaces.