AI Article Synopsis
- The study explores how hydrogenated graphene interacts with an Ir(111) substrate using advanced X-ray techniques, revealing unique absorption profiles and signal intensity changes.
- The researchers refine C 1s X-ray photoelectron spectra to differentiate the effects of hydrogenation in various high-symmetry areas of the graphene structure.
- Results indicate that hydrogenation mainly affects FCC regions, creating a graphane-like structure, while contributions from dimer structures in ATOP regions are minimal, challenging previous assumptions about their significance.
Article Abstract
A combined high resolution X-ray photoelectron spectroscopy and X-ray standing wave study into the adsorption structure of hydrogenated graphene on Ir(111) is presented. By exploiting the unique absorption profiles and significant modulations in signal intensity found within the X-ray standing wave results, we refine the fitting of the C 1s X-ray photoelectron spectra, allowing us to disentangle the contributions from hydrogenation of graphene in different high-symmetry regions of the moiré supercell. We clearly demonstrate that hydrogenation in the FCC regions results in the formation of a graphane-like structure, giving a standalone component that is separated from the component assigned to the similar structure in the HCP regions. The contribution from dimer structures in the ATOP regions is found to be minor or negligible. This is in contrast to the previous findings where a dimer structure was assumed to contribute significantly to the sp part of the C 1s spectra. The corrugation of the remaining pristine parts of the H-graphene is shown to increase with the H coverage, reflecting an increasing number and size of pinning centers of the graphene to the Ir(111) substrate with increasing H exposure.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9409641 | PMC |
| http://dx.doi.org/10.1039/d1fd00122a | DOI Listing |
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