Substrate-Modulated Reductive Graphene Functionalization

• Published in: Angewandte Chemie International Edition Vol. 55; no. 47; pp. 14858 - 14862
• Main Authors: Schäfer, Ricarda A., Weber, Konstantin, Koleśnik-Gray, Maria, Hauke, Frank, Krstić, Vojislav, Meyer, Bernd, Hirsch, Andreas
• Format: Journal Article
• Language: English
• Published: Germany Blackwell Publishing Ltd 14.11.2016; Wiley Subscription Services, Inc
• Edition: International ed. in English
• Subjects: Chemical reactions; Covalence; DFT calculations; functionalization; Graphene; Lattice strain; Microscopy; Monolayers; Raman spectroscopy; Silicon dioxide; Spectroscopy; topicity; functionalization; Raman spectroscopy; DFT calculations; graphene; topicity
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201607427

Covalently functionalizing mechanical exfoliated mono‐ and bilayer graphenides with λ‐iodanes led to the discovery that the monolayers supported on a SiO2 substrate are considerably more reactive than bilayers as demonstrated by statistical Raman spectroscopy/microscopy. Supported by DFT calculations we show that ditopic addend binding leads to much more stable products than the corresponding monotopic reactions as a result of the much lower lattice strain of the reactions products. The chemical nature of the substrate (graphene versus SiO2) plays a crucial role. The rear side of graphene: Mechanical exfoliated graphene was activated and functionalized by λ‐iodane chemistry. The resulting functionalized graphene was analyzed with scanning Raman microscopy. The experimental results were confirmed and explained by DFT calculations. The monolayer graphene was found to be more reactive than bilayer graphene.