title: Highly Intact and Pure Oxo-Functionalized Graphene: Synthesis and Electron-Beam-Induced Reduction.
abstract: Controlling the chemistry of graphene is necessary to enable applications in materials and life sciences. Research beyond graphene oxide is targeted to avoid the highly defective character of the carbon framework. Herein, we show how to optimize the synthesis of oxo-functionalized graphene (oxo-G) to prepare high-quality monolayer flakes that even allow for direct transmission electron microscopy investigation at atomic resolution (HRTEM). The role of undesired residuals is addressed and sources are eliminated. HRTEM provides clear evidence for the exceptional integrity of the carbon framework of such oxo-G sheets. The patchy distribution of oxo-functionality on the nm-scale, observed on our highly clean oxo-G sheets, corroborates theoretical predictions. Moreover, defined electron-beam irradiation facilitates gentle de-functionalization of oxo-G sheets, a new route towards clean graphene, which is a breakthrough for localized graphene chemistry.
authors.affiliation: Institut für Mikro- und Nanostrukturforschung & Center for Nanoanalysis and Electron Microscopy, Friedrich-Alexander-Universität Erlangen-Nürnberg, Cauerstrasse 6, 91058, Erlangen, Germany.
authors.forename: Benjamin
authors.identifier: 0000-0002-9744-3419
authors.initials: B
authors.lastname: Butz
authors.affiliation: Institut für Mikro- und Nanostrukturforschung & Center for Nanoanalysis and Electron Microscopy, Friedrich-Alexander-Universität Erlangen-Nürnberg, Cauerstrasse 6, 91058, Erlangen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Dolle
authors.affiliation: Department of Chemistry and Pharmacy and Central Institute of Materials and Processes (ZMP), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Dr.-Mack Strasse 81, 90762, Fürth, Germany.
authors.forename: Christian E
authors.initials: CE
authors.lastname: Halbig
authors.affiliation: Institut für Mikro- und Nanostrukturforschung & Center for Nanoanalysis and Electron Microscopy, Friedrich-Alexander-Universität Erlangen-Nürnberg, Cauerstrasse 6, 91058, Erlangen, Germany.
authors.forename: Erdmann
authors.initials: E
authors.lastname: Spiecker
authors.affiliation: Department of Chemistry and Pharmacy and Central Institute of Materials and Processes (ZMP), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Dr.-Mack Strasse 81, 90762, Fürth, Germany.|Institut für Chemie und Biochemie, Organische Chemie, Freie Universität Berlin, Takustrasse 3, 14195, Berlin, Germany.|Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Kemivägen 10, 41258, Göteborg, Sweden.
authors.forename: Siegfried
authors.initials: S
authors.lastname: Eigler
keywords: electron microscopy; graphene; graphene derivatives; graphene oxide; reduction