A thorough spectroscopic characterisation of two samples of highly hydrogenated monolayer graphene transferred on nickel grids is herein reported. With X ray photoemission spectroscopy on the C 1s core-level, a 100%sp3 distortion was observed after the hydrogenation of a more sp3-like defected graphene, while a flatter, more sp2-arranged, graphene reached a 62%sp3 saturation. Electron energy loss spectroscopy showed the π-plasmon excitation quenching for the 100%sp3 sample and a significant reduction for the other one. The high loading levels of hydrogenation led to the opening of a wide optical band gap (6.3 and 6.2 eV). The C-H stretching vibrational mode was also observed, as a direct footprint of graphene hydrogenation. Finally, valence band measurements of the 62% saturated sample suggest the coexistence of one-side and two-side hydrogenation morphologies.
@article{arxiv.2504.10238,
title = {Highly Hydrogenated Monolayer Graphene with Wide Band Gap Opening},
author = {Alice Apponi and Orlando Castellano and Daniele Paoloni and Domenica Convertino and Neeraj Mishra and Camilla Coletti and Carlo Mariani and Alessandro Ruocco},
journal= {arXiv preprint arXiv:2504.10238},
year = {2026}
}