Oxo‐Functionalized Graphene: A Versatile Precursor for Alkylated Graphene Sheets by Reductive Functionalization.

Abstract: Controlled covalent functionalization of graphene remains a challenging task owing to the heterogeneous nature of materials. Functionalization approaches for graphene either lack in quantifying the degree of functionalization or they do not discriminate between covalent and non‐covalent functionalization. Here, graphite is oxidized and exfoliated in a three‐step procedure and subsequently reduced and functionalized by hexylation. Although Raman spectroscopy is powerful to determine the degree of in‐plane lattice defects (θ_LD) and functionalization (θ_FD), the method fails at detecting introduced hexyl groups at a concentration of about 0.03 %, next to the pre‐existing in‐plane lattice defects of 0.7 %. However, sensitive thermogravimetric analysis coupled with gas chromatography and mass spectrometry (TGA‐GC/MS) can prove the hexylation reaction. The efficiency of functionalization is comparable to reductive functionalization of pristine chemical vapor deposition (CVD)‐graphene and bulk graphite. [ABSTRACT FROM AUTHOR]