| Organic semiconductive nanocrystal is considered as a novel semiconductor for future organic electronic, where involving a serials advantage as the designable of energy gap of organic semiconductor, highly order molecular packing in crystal, nano-effects in nanomaterial. Herein, a serial of uniform nano-morphology is synthesis, where the symmetry broken driven multi-scale self-assembly is proposed, to investigate the nano effect on the performance of photo-response memory devices. The multi-scale self-assembly of bulky π-system and their opto-electronic properties are summarized as a smart building block. With the respect of the intrinsic feature of organic nanostructure self-assembly, the precisely morphology prediction of micro-/nano- crystal based on thermodynamic mechanism is firstly proposed to guide the multi-scale self-assembly of nano-structures through the calculation of supramolecular interaction energy. Such theory offers a promising method in the design of organic nanostructures. We propose the approach of symmetry broken of suparmolecular interactions under the non-equilibrium conditions, leading to the 1st, 2nd, 3rd symmetry broken of driven forces, as a result of 2D nanosheet, 1D nanowire(or quesi-1D nanobelt) and 3D polyhedra in multi-scales morphology, respectively, where the cruciformed spiro-arene SFX and its derivate are introduced as modeling compounds. Such multi-scale self-assembly further supports the theory of morphology prediction as proposed. The selective adherence of surfactance on the surface of crystal facets is utilized to kinetically synthesis 3D polyhedra and various morphology as bullet shape, octahedron, decahedron et. al., is given out. In order to gain the 2D ultra-thin nano-structures for organic thin-film devices rather than that of thick nanosheet in 1st symmetry broken, the approach of deep symmetry broken is proposed on the supramolecular interactions integrating the advantage of designable of energy gape, where a batch of flexible ultra-thin 2D freestanding nanosheet is obtained in ~10 nm thick, with multi-color emission, uniformity and well-defined shape. The symmetry broken based on non-planar organic semiconductor is proved as a novel strategy in the design of multi-scale organic nanostructures. Such proposed pricple not only enrichs the morphology of organic nano-crystalline semiconductor, but also affords the extending applications of organic nanomaterials in various areas.The synthesis of uniform nano-structure, especially the ultra-thin 2D architecture, is the prerequisite of construction of large area highly quality thin film and provides a novel material supporting as well as the idea model in the mechanism of device operation. The as prepared 2D ultrathin nanosheet is incorporated into highly ordered crystalline uniform thin-film with large area through ecofriendly aqueous processing. The organic diode is designed with such crystalline thin film as the active layer, making use of the nano-tuning effect between nanosheets, and performs a remarkable non-volatile electronic bi-stable feature accompanied by a photo-switching property. Such well-shaped orgnanic semiconductive nanosheets also can be introduced into organic transistor memory as the charge storage element. The so called nano-mosaic transistor memory exhibits a typical multi-bit photo-programmable charge trapping behavior, through the design of nano-mosaic heterojunction with charge transport layer. The excellent charge storage property of devices may due to the highly ordered molecular packing of organic semiconductive nanostructure and the nano-effects at the interface. The organic nano-semiconductor and its hetero-structures with abundant opto-electronic property not only benefit for the construction of high density reliable memory devices, but also potentially for the development of organic opto-electronics towards highly smart behavior. |
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