▎ 摘 要
The multifarious applications of graphene quantum dots (GQDs) necessitate surface modifications to enhance their solution processability. Herein, we report the synthesis and self-assembly of GQDs grafted with poly(epsilon-caprolactone) (PCL) of different degrees of polymerization (3, 7, 15, and 21) produced from ring-opening polymerization. Optical and morphological studies unveil the transformation of the assemblies from J-aggregates to H-aggregates, accompanied by an alteration in morphology from toroid to spheroid to rodlike structures with increasing chain length of PCL. Functionalized GQDs with lower chain lengths of PCL at higher concentration also assemble into liquid-crystalline phases as observed from birefringent textures, which are later correlated to the formation of columnar hexagonal (Col(h)) mesophases. However, no such behavior is observed at higher chain lengths of PCL under identical conditions. Therefore, it is evident that the variation in the PCL chain length plays a crucial role in the self assembly, which is primarily triggered by the van der Waals force between the polymer chains dictating the pi stacking of GQDs, resulting in different self-aggregated behavior.