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利用再沉淀法将Perylene/THF溶液注入甲醇和水的混合溶剂中制备了苝纳米薄片,采用扫描电镜(SEM)、吸收光谱对纳米片形貌和光学特性进行了表征,结果表明,注入不同体积Perylene/THF溶液的苝纳米片表现出不同光学特性,同时对纳米片的形成机制进行了初步的分析和探讨。  相似文献   
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Huicai Ren  Renjie Wang  Zhanxian Gao 《Polymer》2011,52(16):3639-3646
A group of perylene bisimide (PBI) cored dendrimers were designed and synthesized. The polyphenylene dendrons containing carbazole functional groups at periphery were attached to the PBI core with expectation to control the intermolecular interaction and to tune the charge transporting ability of dendrimers. Their photophysical, electrochemical and thermal properties were investigated. The spectral data showed that energy transfer and photoinduced charge transfer coexist between the carbazole peripheries and the PBI core, competing to influence the luminescent properties of these dendrimers. The red OLEDs were fabricated with these dendrimers as non-doped emitting layer by solution method. The dendrimers bearing carbazoles exhibited improved EL performance than those model compounds. The improved charge balance state caused by these carbazole units is suggested to be responsible for the EL performance.  相似文献   
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Perylene diimides (PDIs) are one of the most widely studied n‐type materials, showing great promise as electron acceptors in organic photovoltaic devices and as electron transport materials in n‐channel organic field effect transistors. Amongst the well‐established chemical modification strategies for increasing the electron mobility of PDI, substitution of the imide oxygen atoms with sulfur, known as thionation, has remained largely unexplored. In this work, it is demonstrated that thionation is a highly effective means of enhancing the electron mobility of a bis‐N‐alkylated PDI derivative. Successive oxygen–sulfur substitution increases the electron mobility such that the fully thionated derivative ( S4 ) has an average mobility of 0.16 cm2 V?1 s?1. This is two orders of magnitude larger than the nonthionated parent compound ( P ), and is achieved by solution deposition and without thermal or solvent vapor annealing. A combination of atomic force microscopy and 2D wide angle X‐ray scattering experiments, together with theoretical modeling of charge transport efficiency, is used to explain the strong positive correlation observed between electron mobility and degree of thionation. This work establishes thionation as a highly effective means of enhancing the electron mobility of PDI, and provides motivation for the development of thionated PDI derivatives for organic electronics applications.  相似文献   
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以苝四酸酐为原料合成了作为铅荧光探针的一种新型水溶性荧光衍生物N,N'-二谷氨酸铵盐-3,4,9,10-苝四羧酸二酰亚胺(PTCDG),其结构已经1H NMR和IR证实。研究了PTCDG及PTCDG与金属离子(M)络合物(PTCDG/M)的光谱性质和PTCDG对金属离子的识别性能。结果表明,PTCDG在水溶液中能与Pb2+有较强的螯合作用,两者络合比为1∶1,Pb2+可有效淬灭PTCDG的荧光且PTCDG对Pb2+识别作用不受Mn2+, Mg2+, Zn2+, Ni2+, Ca2+, Co2+, Na+, K+, Ba2+ , Hg2+等金属离子干扰。本文还对PTCDG与金属离子作用的荧光变化机理做了探讨。  相似文献   
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A new electrontransport polymer, poly{[N,N′‐dioctylperylene‐3,4,9,10‐bis(dicarboximide)‐1,7(6)‐diyl]‐alt‐[(2,5‐bis(2‐ethyl‐hexyl)‐1,4‐phenylene)bis(ethyn‐2,1‐diyl]} (PDIC8‐EB), is synthesized. In chloroform, the polymer undergoes self‐assembly, forming a nanowire suspension. The nanowire's optical and electrochemical properties, morphological structure, and field‐effect transistor (FET) characteristics are investigated. Thin films fabricated from a PDIC8‐EB nanowire suspension are composed of ordered nanowires and ordered and amorphous non‐nanowire phases, whereas films prepared from a homogeneous PDIC8‐EB solution consist of only the ordered and amorphous non‐nanowire phases. X‐ray scattering experiments suggest that in both nanowires and ordered phases, the PDIC8 units are laterally stacked in an edge‐on manner with respect to the film plane, with full interdigitation of the octyl chains, and with the polymer backbones preferentially oriented within the film plane. The ordering and orientations are significantly enhanced through thermal annealing at 200 °C under inert conditions. The polymer film with high degree of structural ordering and strong orientation yields a high electron mobility (0.10 ± 0.05 cm2 V?1 s?1), with a high on/off ratio (3.7 × 106), a low threshold voltage (8 V), and negligible hysteresis (0.5 V). This study demonstrates that the polymer in the nanowire suspension provides a suitable material for fabricating the active layers of high‐performance n‐channel FET devices via a solution coating process.  相似文献   
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