Design, Synthesis And Properties Study Of Sandwich Phthalocyaninato Complexes/Perylenetetracarboxylic Diimides

Owing to the unique optical, electrical, and properties, associated with the intriguingintramolecular π-π interactions, perylenetetracarboxylic diimides, phthalocyanines, inparticular sandwich type rare complexes, as a novel functional materials, have been expectedto be widely potential application in materials science, such as in molecular electronics,molecular information storage, and nonlinear optics, etc. Recently, it is significantlyinterested in ordered supramolecular aggregate and nanoscale assembly fields. However, itmust be pointed out that self-assembly of functional molecules into a prerequisitenanostructure with desirable dimension and morphology via controlling and optimizinginter-molecular interaction still remains a great challenge for chemists and material scientists.In order to extensively investigate supramolecular aggregation behaviors and supramolecularassembly methodology of perylenetetracarboxylic diimides and phthalocyninato complexes,in this thesis a series of perylenetetracarboxylic diimides and phthalocyanine derivatives areselected, and some modern measuring techniques were performed to examine their aggregatestructures, morphologies and nanostructures. Our research work has been focused on thefollowing respects:1. Organic/inorganic self-Assembled film based on a perylenetetracarboxylic diimidederivative/CdSA perylenetetracarboxylic diimide derivative, N,N,N′,N′-tetra（hydroxyethyl）-1,7-di（4-tert-butylphenol）perylene-3,4:9,10-tetracarboxylic diimide（THPDI）, was synthesized andcovalently self-assembled as a monolayer on the modified a quartz surface. UV-vis absorptionand IR spectra revealed the H-aggregate nature of THPDI molecules in the obtained thin solidfilm. With this thin solid film as a template, CdS nanoparticles were deposited on it in situ,which were characterized by electronic absorption, X-ray photoelectron spectroscopy （XPS）and atomic force microscopy （AFM）. The morphology of CdS nanoparticles is disklike, andthe diameter is ca.150nm as determined by AFM. The present result provides an effectiveand new method toward directed growth of specific morphologies of the nanoparticles. It isbelieved helpful for designing and preparing molecular-based nano-electronic and nano-optoelectronic devices with good performance.2. Synthesis of a symmetric substituted perylenetetracarboxylic diimide derivative（HOPDIOH） and the properties of the resulting HOPDIOH/CdS hybrid systemA new perylene tetracarboxylic diimides named asN,N′-di（hydroxyethyl）-1,7-di（4-tert-butylphenol）perylene-3,4,9,10-tetracarboxydiimide（HOPDIOH） has been synthesized successfully. A self-assembly film is fabricated through anester bond between the-OH groups in HOPDIOH molecules and-COOH groups on modifiedSiO₂slice. The uniformed surface morphology with elongated domains in the range of ca.50-70nm was obversed by atomic force microscopy （AFM）. Then this film is used as atemplate, and CdS nanoparticles are deposited on it in situ, resulting HOPDIOH/CdS hybridsystem. XPS analysis confirmed unambiguously the existence of CdS in it. The morphologyof CdS nanoparticles is disklike, and the diameter is ca.100nm as determined by AFM. Themeasurements of electronic absorption and fluorescence spectra revealed that, highly orderedof HOPDIOH self-assembled film has been formed in which the molecular arrangement ofHOPDIOH was found in J-aggregation mode. Fouthermore, a energy transfer from CdS toHOPDIOH was found in HOPDIOH/CdS hybrid system, by comparative study of emissionspectra and fluorescence lifetime between HOPDIOH self-assembled film and HOPDIOH/CdS hybrid films. In order to study the potential of such systems as semiconductor devices,the conducting properties of HOPDIOH/CdS hybrid films were evaluated by current-voltage（I-V） measurements in nitrogen and air, respectively. The conductivity of the films of eitherHOPDIOH self-assembled film or HOPDIOH/CdS hybrid films measured in N₂is higherthan thosein air, impling n-type semiconductor properties. In particular, HOPDIOH/CdShybrid films show excellent semiconducting property with the electrical conductivity up to8.5×10^-4Scm^-1, which might serve as promising candidates for applications innano-electronics.3. Design and synthesis of air stable n-type three-phthalocyanine rare earth complexes: Effectof molecular aggregation mode on the semiconductor natureWe designed and synthesized a new semiconductor family of heteroleptic and homoleptic tris（phthalocyaninato） rare earth（III） complexes, namely Eu₂[Pc（OPh）₈]₃（1） andEu₂（Pc）[Pc（OPh）₈]₂（2）[Pc=unsubstituted phthalocyaninate; Pc（OPh）₈=2,3,9,10,16,17,23,24-octaphenoxyphthalocyaninate].Two new sandwich compounds have been characterized with various spectroscopicmethods. Their film forming and organic field effect transistor properties have been studied.Experimental results showed that two sandwich triple-deckermolecules have been fabricatedinto highly ordered films by the quasi-Langmuir-Sh fer （QLS） method. In the QLS films,compound1adopt the H aggregation mode, whereas compound2adopt J aggregation mode,respectively, implying the effect of substituent on tuning the intermolecular stacking. The airstable n-type OTFT activities are demonstrated for both1and2, which can be rationalized onthe basis of their modest HOMO and LUMO energy levels. The largest electron mobility of0.82cm²/Vs for1revealed for this new family of molecular materials can be correlated withfavorable molecular packing, thin-film microstructure, and morphology as revealed byUV-vis, XRD and AFM characterizations.