Octylamine‐Modified Fluorographenes as a Versatile Platform for the Efficient Engineering of the Nonlinear Optical Properties of Fluorinated Graphenes

Fluorographene (FG) is an uprising member of the graphene family as it combines high reactivity and stability. It presents various types of C -F bonds (covalent, semi-ionic, and ionic bonds) depending on its F-atom content, which can be efficiently controlled by means of chemical synthesis. It is found that the chemical tweaking of the FG's structure may lead to derivatives such as aminoand thiol-modified FGs, affecting significantly their nonlinear optical (NLO) response. Herein, the identification of N-octylamine (OA) as the most efficient nucleophile is reported on, which ascribes to the obtained FG-OA derivatives exceptionally high N content (up to 18%) along with a record NLO response under 35 ps laser pulses, both in the visible and the infrared. As the reaction time between FG and OA proceeds, the F content declines at the expense of the growing aromatic regions and nitrogen centers, resulting in FG-OA materials with progressively improved NLO response. Therefore, OA functionalization of FG is particularly effective for switching "ON" an unprecedented NLO response on this organophilic graphene derivative. Herein, the potential of fluorinated graphene as a versatile scaffold is also demonstrated, allowing the preparation of materials with custom-made NLO response.