Dr. Jose Perez Research Group

We are currently working on two-dimensional materials, particularly graphene and molybdenum disulfide. We recently started a  project on hydrogen storage in graphene using electron irradiation of graphene at atmospheric pressure. This project is funded by the National Science Foundation for three years, starting August 1, 2023. We aim to determine if the defects formed during electron irradiation are hydrogen adsorbates. We believe this is the case, and the mechanism is the electron-induced dissociation of adsorbed water into hydrogen that then adsorbs on the graphene.  We will use tagged mass spectroscopy, scanning tunneling microscopy, Raman spectroscopy, and x-ray photoelectron spectroscopy to determine if the adsorbates are hydrogen.  We are currently recruiting undergraduate and graduate students for this project. We will update this site as the project develops.

Results of Irradiating Graphene

When we irradiate graphene with electrons at increasing dosages using a scanning electron microscope, a D peak is observed that follows a previously published model as we recently published in J. Vac. Sci. Technol. A 41 (1) Jan/Feb 2023; doi: 10.1116/6.0002209.

Thermal Annealing

After we thermally anneal the irradiated sample, we find an activation energy for defect healing of 0.48 eV. This activation energy is consistent with the defects being adsorbed hydrogen. Reference: J. Vac. Sci. Technol. A 41 (1) Jan/Feb 2023; doi: 10.1116/6.0002209.

Picture of our UHV STM and Surface Analysis System

We will be using STM, tagged mass spectroscopy, Raman spectroscopy, XPS and other techniques to identify the adsorbates.

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