Study On The Self-assembly Structures Of Perylene And Pyrene Derivatives

With the rapid developments of organic optoelectronic devices, such as organic light-emitting diodes(OLED). organic solar cells and organic field-effect transistors(OFET) and so on, the organic materials with π-conjugated chromophores have attracted more interest of scientists. Having larger π-conjugated system, perylene derivatives and pyrene derivatives have potential application value in the new photoelectric materials.In this thesis, Carboxylate of perylene anhydride.1.3,6,8-pyrenetetra sulfonic acid tctrasodium salt and cationic surfactants (DOAB and DHAB) were selected as raw materials to synthesize two new types of perylene derivatives and pyrene derivatives at room temperature by a ionic self-assembly method. NMR and FT-IR were used to determine the composition and structure of.the target products. TEM, XRD, SAXS, UV-Vis spectra and fluorescence spectra were also used to characterize the self-assembled morphology of gelation aggregates, gelation mechanism, the arrangement of structure and fluorescence features, etc. The molecular models of the gel aggregates were built according to experimental data.The results show that:(1) Comparing the traditional method, there are several advantages using the ionic self-assembly method, such as shorter reaction time, higher yield and non-polluting.(2) In the appropriate solvent, perylene derivatives and pyrene derivatives are able to self-assemble into ordered aggregates through the π-π stacking of the aromatic ring.(3) Perylene derivative (PTCT-DOAB) and pyrene derivative (PyATS-DOAB) could form gels in toluene. These gels showed typical layered structures, perylene ring and pyrene ring formed one-dimensional structures through π-π stacking and alkyl chains twisted through van der Waals force. There was a kind of competition between gelation and crystallization in the formation of Perylene derivatives PTCT-DOAB gelation.(4) The mixture of perylene derivatives and pyrene derivatives could also form gelation in toluene. These two types of derivatives could form gelation separately in the mixture, the results showed that the recognition of π-π stackin between the perylene and pyrene was very strong and only could recognise the same type of moleculars. The main driving force of gelation was the strong π-π stacking between the aromatic rings and van der Waals forces between the disorder alkyl chains.(5) Perylene derivatives PTCT-DOAB’s and pyrene derivatives PyATS-DOAB’s ethanol solution or toluene solution had typical fluorescence under the UV-lamp. PTCT-DOAB distributed yellow-green fluorescence and PyATS-DOAB distributed blue fluorescent.