Graphene Oxide Synthesis and Radiolysis

Open Access
Author:
Wetherington, Maxwell Turner
Graduate Program:
Materials Science and Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
June 07, 2013
Committee Members:
  • Joshua Alexander Robinson, Thesis Advisor
  • David Lawrence Allara, Thesis Advisor
  • James Hansell Adair, Thesis Advisor
Keywords:
  • graphene oxide
  • functionalization
  • radiolysis
  • luminescence
Abstract:
The diverse functionalization of graphene oxide (GO) provides this material unique chemical and physical properties that can theoretically be tailored during the synthesis and/or reduction of the material. One specific property of interest for the opto-electronic industry is the ability to tailor the optical band gap of GO, which can be modified by selective functionalization or through the formation of heterogeneous structures. Understanding the mechanisms through which this functionalization can be controlled is necessary before GO can be implemented into these opto-electronic devices. This thesis investigates the effects of the synthesis process on the GO structure; identifying key parameters for the oxidation method, cleaning procedure and starting material selection. It is determined that water significantly affects the present functional groups in GO. Also the size of the GO flakes correlates with the crystallite size of the graphite material, as well as the starting flake size. The stability of this structure is then explored through the use of in-situ x-ray techniques. A range of photon radiation sources are used for the in-situ measurements to identify the rate of interaction as a function of photon energy as well as the interaction mechanisms. Lastly, the interaction of GO with other ionizing radiation, such as neutron and alpha particles, is investigated.