| Recently, supramolecular chemistry ofπ-conjugated materials have attracted increased interest, which provides an efficient tool to explain many optoelectronic phenomenon and construct nanostructures with distinct size, shape and function. Supramolecular chemistry, a term introduced by Jean-Marie Lehn, is"chemistry beyond the molecule", that is the chemistry of molecular assemblies using noncovalent bonds. Its main features are: (1) weak noncovalent forces can become much stronger when they cooperatively combine together. (2) supramolecular self-assembly ofπ-conjugated systems can attribute many new features to the single molecules. In crossing with material science, supramolecular chemistry plays an important role in creating new functions of materials and extends the application field ofπ-conjugated systems to nanoscience and biology. This thesis is mainly focused on studying the influences of supramolecular interactiontions on optoelectronic properties of organicπ-conjugated materials.In foretime study, we find that theπ-πdistance and stacking style have great effect on the properties of organicπ-conjugated materials. The"face-to-face"π-πstacking can increase the electronic couple and increase the material mobility.In fact, the real stcacking style is"edge-to-face"because of lower energy in usual.Recently, hydrogen-bond directed self-assemblies ofπ-conjugated system have been extensively studied. The synergetic combination ofπ-stacking and hydrogen bonding is found important for the future development of supramolecular electronics based on such hybrid systems, where long-range order, high charge carrier mobility and thermal stability are prerequisites. In this paper, a series of bisurea-end capped oligo(p-phenylenevinylene)s (OUPVs) have been synthesized and fully characterized. In OUPVs, the urea groups (hydrogen-bond motifs) are covalently linked with OPVs (π-conjugated moieties) without any spacers to unify the two forces into interlocked hydrogen bond andπ-πinteractions; the urea-urea hydrogen bonds are enabled in theπ-stacking direction to construct balanced supramolecular interactions. Through careful tuning and design, urea-urea associations at both ends of theπ-conjugated moiety can provide a forceful framework for"face-to-face"π-πstacking due to the synergetic combination of different interactions at the molecular level. A broad range of analytical methods have been used to study the aggregation behavior of the molecules. It is found that the OUPV molecules can self-assemble into supramolecular wires with lengths up to tens of microns that exhibit intense electronic coupling, high molecular ordering and extraordinary thermal stability.We have synthesized a series of molecular with the similar structure to OUPVs but the kind and position of the function group are changed. All analysis result are used to investigate how the intermolecular foces and cooperative effect to impact on the aggeragating style, the extent of electronic coupling, the molecular ordering and the thermal stability. The alkoxy chains substituted on the centralπblocks exhibit great influences to the molecular aggregate behaviors, (including decreaseing the molecular ordering and thermal stability) because the alkoxy chains can weak the the synergetic combination ofπ-πwith hydrogen-bond. Another kind of bisurea-end capped oligo(p-phenylenevinylene)s (i-OUPVs) have been synthesized and fully characterized. In i-OUPVs, there is a short alkoxy chains between the urea groups (hydrogen-bond motifs) and OPVs (π-conjugated moieties). We find that the"face-to-face"π-πstacking style of OUPVs is due to the synergetic combination of different interactions at the molecular level, includingπ-πwith hydrogen-bond andπ-πwith van der waals force. This kind of cooperative effect including two features: (1).the different intermolecular forces should stimulate each other, not counteract eath other for some special material function; (2).the entire intermolecular force is not adding all force simply, it can produces 1+1>2. The synergetic combination of different interactions at the molecular level can play a great role in the supramolecular self-assembly aggregation process.
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