2026-06-23T13:02:54Z https://archive.materialscloud.org/oai2d

oai:materialscloud.org:1683 2025-12-16T14:19:02Z openaire_data community-mcarchive

Bonacci, Miki Bonacci, Miki Molinari, Elisa Prezzi, Deborah 2023-03-10 The conversion of semimetallic suspended graphene (Gr) to a large-gap semiconducting phase is realized by controlled adsorption of atomic hydrogen (deuterium) on free-standing Gr veils in nanoporous graphene. The effects of local rehybridization from sp² to sp³ chemical bonding are investigated by combining X-ray photoelectron spectroscopy and high-resolution electron energy-loss spectroscopy (HREELS) with ab-initio based modelling. The hydrogen adatoms on the C sites induce a stretching frequency, clearly identified in vibrational spectra thanks to the use of the D isotope, which is compatible with the predicted fingerprints of adsorption on both sides of Gr corresponding to the graphane configuration. HREELS of the deuterated samples shows a wide opening of the optical band gap, consistent with the modified spectral density observed in the valence band photoemission. The results are in agreement with ab-initio calculations by GW and Bethe-Salpeter equation approaches, showing a large quasiparticle gap opening and huge excitonic binding energy application/gzip application/gzip application/json text/markdown text/plain https://doi.org/10.24435/materialscloud:9b-34 oai:materialscloud.org:1683 mcid:2023.40 eng Materials Cloud https://doi.org/10.1016/j.cartre.2023.100274 https://archive.materialscloud.org/communities/mcarchive https://doi.org/10.24435/materialscloud:g2-43 info:eu-repo/semantics/openAccess Creative Commons Attribution 4.0 International https://creativecommons.org/licenses/by/4.0/legalcode BIG-MAP BSE first principles hydrogenated graphene nanoporous graphene MaX Yambo code density-functional theory high-resolution electron energy-loss spectroscop HREELS Dielectric response and excitations of hydrogenated free-standing graphene info:eu-repo/semantics/other