Organic Materials for Optoelectronic Technologies

[9985632]有机半导体材料在一系列新兴技术中产生了广泛的影响。最近在材料合成方面的努力，结合器件工程，在制造有机基发光二极管、薄膜晶体管、固态激光器、太阳能电池和光电探测器方面达到了顶峰。甚至有人猜测，为计算目的而创造的全有机电路。所有这些功能的基础是固体中有机发色团之间的空间关系，以及该参数控制不同亚基之间电子耦合的方式。此外，固体中的有序水平决定了小分子材料形成稳定的非晶膜的能力以及它们在器件结构中的潜在包裹体。这项提案在未来一年的目标是双重的。首先是发展必要的方法来制备具有几何属性的定义良好的分子，从而产生非晶材料。这种类型的材料可以比聚合物更大程度地纯化，并且在小浓度污染物不成比例地影响电荷迁移的设备中提供优势。第二个目标是用上述化合物制造器件，并利用所得的性能曲线来探测分子形状对体电荷传输能力的影响。资助期间的具体目标是：(1)合成具有四面体几何形状的结构精确共轭有机分子。我们感兴趣的将是研究拓扑如何转化为体形态。将进行光谱学研究，以更好地了解具有高生色团含量的有机玻璃中存在的环境类型和可变性。这将通过将溶剂化变色染料掺入有机非晶薄膜中并通过测量所得到的光学性质来实现。这里的最终目标是制定指导方针，允许在无序系综中调整发色团的协同性，并更好地理解可能存在于无定形有机固体中的局部秩序。（二）利用上述材料制造发光二极管。对器件性能的分析将提供有用的见解，了解分子形状如何影响重要的体性质，如电导率和电致发光量子产率。

9985632BazanOrganic semiconducting materials are making a widespread impact in a range of emerging technologies. Recent efforts in materials synthesis, in conjunction with device engineering, has culminated in the fabrication of organic-based light emitting diodes, thin film transistors, solid state lasers, solar cells and photodetectors. There is even speculation about the creation of all-organic circuitry for computing purposes. Underlying all these functions is the spatial relationship between organic chromophores in the solid and the manner by which this parameter controls the electronic coupling between different subunits. Additionally, the level of order in the solid determines the ability of small molecule materials to form stable amorphous films and their potential inclusion into device structures.The goals of this proposal over the next year are twofold. The first is to develop the necessary methodology to prepare well-defined molecules with geometrical attributes that yield amorphous materials. Materials of this type can be purified to a greater extent than polymer counterparts and offer advantages in devices where a small concentration of contaminants disproportionately affects charge migration. The second aim is to fabricate devices with the above compounds and to use the resulting performance profiles to probe the effect of molecular shape on the charge transport ability of the bulk. The specific objectives during the grant period are:(1) The synthesis of structurally-precise conjugated organic molecules with tetrahedral geometries. Of interest will be to examine how topology translates into bulk morphology. Spectroscopic studies will be executed to understand better the types and variability of environments present in organic glasses with a high chromophore content. This will be achieved by incorporating solvatochromic dyes into organic amorphous films and by measuring the resulting optical properties. The ultimate goal here is to develop guidelines that allow for tuning the cooperativity of chromophores in a disordered ensemble and to develop a better understanding of the local order that may exist in amorphous organic solids.(2) To fabricate light emitting diodes using the above materials. Analysis of device performance will provide useful insight into how molecular shape affects important bulk properties such as conductivity and electroluminescence quantum yield.