<?xml version='1.0' encoding='utf-8'?> <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> <dc:creator>Bonacci, Miki</dc:creator> <dc:creator>Molinari, Elisa</dc:creator> <dc:creator>Prezzi, Deborah</dc:creator> <dc:date>2023-03-10</dc:date> <dc:description>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</dc:description> <dc:identifier>https://archive.materialscloud.org/record/2023.40</dc:identifier> <dc:identifier>doi:10.24435/materialscloud:9b-34</dc:identifier> <dc:identifier>mcid:2023.40</dc:identifier> <dc:identifier>oai:materialscloud.org:1683</dc:identifier> <dc:language>en</dc:language> <dc:publisher>Materials Cloud</dc:publisher> <dc:rights>info:eu-repo/semantics/openAccess</dc:rights> <dc:rights>Creative Commons Attribution 4.0 International https://creativecommons.org/licenses/by/4.0/legalcode</dc:rights> <dc:subject>BIG-MAP</dc:subject> <dc:subject>BSE</dc:subject> <dc:subject>first principles</dc:subject> <dc:subject>hydrogenated graphene</dc:subject> <dc:subject>nanoporous graphene</dc:subject> <dc:subject>MaX</dc:subject> <dc:subject>Yambo code</dc:subject> <dc:subject>density-functional theory</dc:subject> <dc:subject>high-resolution electron energy-loss spectroscop</dc:subject> <dc:subject>HREELS</dc:subject> <dc:title>Dielectric response and excitations of hydrogenated free-standing graphene</dc:title> <dc:type>Dataset</dc:type> </oai_dc:dc>