Mechanical Exfoliation of Expanded Graphite and Functionalization with Palladium Nanoparticles for Hydrogen Storage
Due to the clear effect of fossil fuels on the environment, alternative sources of energy must be considered. One alternative is hydrogen which is abundant and does not produce greenhouse gasses. The advent of a hydrogen economy is a challenge due to the requirement of a safe and efficient storage method. In this thesis, a graphene-based nanomaterial was prepared through liquid phase exfoliation of expanded graphite (EG) followed by functionalization with palladium nanoparticles (Pd-NP) as a solid-state hydrogen storage material. Specifically, high-shear mixing and probe-tip sonication produced palladium functionalized sonicated EG (Pd-sEG) and palladium functionalized sheared EG (Pd-ShEG). A variety of characterization methods were used, and the hydrogen storage ability was assessed through electrochemical studies. It was determined the hydrogen desorption charge was 50.4 mC cm-2 for Pd-sEG, and 41.2 mC cm-2 for Pd-ShEG, notably improving the performance over base materials of Pd-EG (29.6 mC cm-2) and Pd-NP (19.2 mC cm-2).