Self-assembly Of Peryleneimide Derivatives

Peryleneimide derivatives(PDIs)are n-type organic semiconductor molecules having a largeπ-πconjugated system based on a perylene ring central structure and have been widely used as a compound with excellent optical,thermal and chemical stability used in dyes,optoelectronics,self-assembly,biological imaging and other fields.Multifunctionalization of PDI can be achieved by introducing different functional groups through chemical modification.In this paper,we study the relationship between molecular structure and self-assembled properties ofπ-conjugated system based on peryleneimine,and the self-assembly behaviors based on charge-transfer interactions.The main contents are as follows:1.In the first part of our work,we systematically investigated the effect of hydrogen bonding on the self-assembly of perylene-imide molecules(PMAMI and PDINH)in solution and at the liquid-solid interface.Among them,PDINH has internal hydrogen bonding sites,while PMAMI molecules do not contain hydrogen bonds.When MeOH are added to the THF solution of both molecules,PMAMI and PDINH show different assembly properties when different proportions of poor solvent.For PDINH,the main driving forces were hydrogen bonds from imide groups andπ–πstacking from the PI cores.For PMAMI,π–πstacking primarily facilitates the aggregation of PI cores.This investigation provides an alternative strategy to design and fabricate perylene imide-based derivatives for potential applications2.In the second part of our work,the effect of the linear alkyl-chain length on the self-assembly of PBIs with substituents on bay positions(C6-PBI and C12-PBI)has been systematically investigated.In this investigation,THF was used as the good solvent and methanol as the poor solvent.The percentage volume of MeOH(C_M,v%)in the solvent was altered to change the solvent polarity and induce the self-assembly of PBIs.By comparing the morphologies and spectral data of the two molecules,it was proposed that π-πstacking dominated the assembly of C6-PBI,whereas bothπ-πstacking and van der Waals interactions contributed to the hierarchical assembly of C12-PBI.Studies have confirmed that the length of the alkyl chain of the perylene core end group can regulate the assembly behavior of the perylene imide molecule.Then the alkyl chain effect,especially from the linear ones,should be considered on designing new PBI-based uilding blocks and constructing supramolecular nanostructures and materials.3.In the third part,we used NDI(~6.7?)and PDI(~11?)molecules with different conjugated aromatic cores as the acceptors,pyrene derivatives as electron-rich donors to gain insight into the dimension size impact on formation of CT organogels.The results fully demonstrate that the difference in conjugation size(length)leads to differences in the mechanism of CT interaction.Inside the assembly structure,NDI tends to alternate with the crucible,while PDI molecules have a stronger self-aggregation ability.Our investigations provided opportunities to fabricate CT based functional materials.