Melaku A.ZChuang W.-TShieh Y.-TChiu C.-WLee D.-JLai J.-YCheng C.-C.DUU-JONG LEE2022-03-222022-03-22202120521537https://www.scopus.com/inward/record.uri?eid=2-s2.0-85115348445&doi=10.1039%2fd1qm00810b&partnerID=40&md5=bd60eac9b84f5ece5e6ddd8771906897https://scholars.lib.ntu.edu.tw/handle/123456789/598166Programmed formation of hierarchical graphene nanosheets, based on a combination of first and second exfoliations using the halogenated solvent ortho-dichlorobenzene (ODCB) and an adenine-functionalized supramolecular polymer (A-PPG), respectively, can be used to directly exfoliate graphite into high-quality graphene nanosheets with wide-range tunable layer thickness. In this study, we discover that natural graphite in ODCB can be directly exfoliated into well-dispersed, dozen-layer exfoliated graphite (EG) nanosheets with relatively weak interlayer interactions; this process is called first exfoliation. On subsequent addition of A-PPG into the EG solution (i.e., second exfoliation), the hydrogen-bonded adenine moieties act as indispensable key units that manipulate the self-assembly behavior of the A-PPG polymers to effectively form long-range ordered lamellar nanostructures on the surface of the graphene nanosheets. This process substantially enhances the long-term dispersion stability of EG in ODCB and achieves the production of exfoliated graphene nanosheets with the desired structural characteristics through simply adjusting the content of A-PPG in the composites. These desirable characteristics of non-covalently functionalized graphene with a supramolecular polymer are extremely rare, but highly attractive for the development of physically custom-tailored graphene based on combined first and second exfoliation processes. Thus, this development provides a facile, highly efficient graphene fabrication process for potential applications in various fields. This journal is ? the Partner Organisations.Exfoliation (materials science)GraphiteHalogenationHydrogen bondsNanosheetsSelf assemblySupramolecular chemistryDynamic self-assemblyExfoliated graphiteFunctionalizedGraphene nanosheetsHalogenated solventsHigh qualityLayer thicknessOrtho-dichlorobenzeneSupramolecular polymersTunablesGraphenejournal article10.1039/d1qm00810b2-s2.0-85115348445