title: Probing the chemical structure of monolayer covalent-organic frameworks grown via Schiff-base condensation reactions.
abstract: Two-dimensional covalent-organic frameworks (2D-COFs) on surfaces offer a facile route to new 2D materials. Schiff-base condensation reactions have proven to be an effective fabrication route for such materials. We present scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS) studies of porphyrin 2D-COFs grown at a solid-vapour interface. XPS shows that covalent links between porphyrins consist of a mixture of imines and hemiaminals, a non-conjugated intermediate in the Schiff-base condensation reaction. These results demonstrate that environmental conditions during growth can have an important impact on the chemical composition of Schiff-base 2D-COFs.
authors.affiliation: Department of Chemistry, University College London (UCL), 20 Gordon Street, London, WC1H 0AJ, UK. m.blunt@ucl.ac.uk.
authors.forename: Ya
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Department of Chemistry, University College London (UCL), 20 Gordon Street, London, WC1H 0AJ, UK. m.blunt@ucl.ac.uk.
authors.forename: Niall
authors.initials: N
authors.lastname: Goodeal
authors.affiliation: Department of Chemistry, University College London (UCL), 20 Gordon Street, London, WC1H 0AJ, UK. m.blunt@ucl.ac.uk.
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Chemistry, University College London (UCL), 20 Gordon Street, London, WC1H 0AJ, UK. m.blunt@ucl.ac.uk.
authors.forename: Alex M
authors.initials: AM
authors.lastname: Ganose
authors.affiliation: Department of Chemistry, University College London (UCL), 20 Gordon Street, London, WC1H 0AJ, UK. m.blunt@ucl.ac.uk.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Palgrave
authors.affiliation: Department of Chemistry, University College London (UCL), 20 Gordon Street, London, WC1H 0AJ, UK. m.blunt@ucl.ac.uk.
authors.forename: Hugo
authors.initials: H
authors.lastname: Bronstein
authors.affiliation: Department of Chemistry, University College London (UCL), 20 Gordon Street, London, WC1H 0AJ, UK. m.blunt@ucl.ac.uk.
authors.forename: Matthew O
authors.initials: MO
authors.lastname: Blunt