Electronic Phenomena at the Hetero-Nanointerface Fabricated from Self-Assembled Films and Photoelectric Conversion Devices

最近，对有机材料在电子器件中的实际应用的研究取得了优异的成果。认为主链上具有高度扩展π-电子共轭体系的导电聚合物是一种很有前途的有机电子器件材料。由于导电聚合物/金属或导电聚合物/导电聚合物组成的界面在聚合物电子器件中是必不可少的，因此界面上的电子现象对此类器件的性能和功能至关重要。接口属性会影响器件的基本属性。因此，不仅需要了解导电聚合物本身的性质，还需要了解纳米尺度上的界面电子现象和电子态。本文提出了一种新的薄膜加工技术，用于制备具有分子水平厚度控制和多层电弧结构的导电聚合物超薄膜。这种新的自组装工艺为需要大面积超薄导电聚合物薄膜的应用开辟了广阔的可能性，更重要的是，它可以利用多层薄膜复杂的超分子结构中可实现的独特相互作用。研究了聚吡啶、PPy/聚（2-甲氧基-5-十二烷基-对苯基乙烯基）、MDOPPV异质结构光电转换装置的光辐照效应。该异质结构光电转换器件的光伏特性较单层光电转换器件有较大改善，较单层光电转换器件有较大改善。在PPy/MDOPPY异质结构薄膜中也观察到PPy层膜和MDOPPV层膜的光致发光猝灭现象。观察到的异质结构器件的光照射效应表明，在PPy和MDOPPV之间发生了光诱导电荷转移。然而，这些聚合物之间的光致电荷转移不能用聚合物的体电子能态来解释。提出了一种可能的机制，该机制考虑了由于局部晶格畸变而引起的界面电子能态的调制。研究了空气中导电聚合物/电极界面处的电子态。研究了导电聚合物薄膜表面的费米能级（E_F）和电离势（Ip）随薄膜厚度的变化规律。用开尔文探针法测定了导电聚合物表面的E_f，用大气光电子能谱法测定了Ip。当电极材料为Al时，EF对膜厚的依赖性与Ip有很大不同。少

Recently, research into the practical use of organic materials in electronic devices has produced excellent results. It is considered that conducting polymers with highly extended π-electron conjugated systems in their main chains are highly promising materials for organic electronic devices. Because interfaces consisting of condicting polymer/metal or conducting polymer/conducting polymer are necessary in polymer electronic devices, the electronic phenomenon at the interface is critically important to the performance and the function of such devices. The fundamental device properties are affected by interfacial properties. Accordingly, it is necessary to understand not only the properties of the conducting polymer itself, but also interfacial electronic phenomena and electronic states on a nanometer scale.A novel thin film processing technique has been developed for the fabrication of ultrathin films of conducting polymers with molecular level control over thickness and multilayer arc … More hitecture. This new self-assebly process opens up vast possibilities in applications which require large area ultrathin films of conducting polymers and more importantly in applications that can take advantage of the unique interactions achievable in the complex, supermolecular architectures of multilayer films.Photoirradiation effects of a polypyridine, PPy/poly(2-methoxy-5-dodecylozy-p-phenylene vinylene), MDOPPV heterostructure photoelectric conversion device have been investigated. The photovoltaic characteristics of the heterostructure photoelectric conversion device are considerably improved from those in single-layer photoelectric conversion device are considerably improved from those in single-layer photoelectric conversion devices. Quenching of photoluminescence both in the PPy layer film and in the MDOPPV layer film has also been observed in the PPy/MDOPPY heterostructure film. The observed photoirrsdiation effects of the heterostructure device indicate that a photoinduced charge transfer occurs between PPy and MDOPPV. However, the photoinduced charge transfer between these polymers cannot be explained by the bulk electronic energy states of the polymers. A possible mechanism, which takes modulation of electronic energy states at the interface due to a local lattice distortion into account, has been proposed.The electronic state at the conducting polymer/electrode interface in air was investigated. The Fermi level (E_F) as well as the ionization potential (Ip) at the surface of conducting polymer films coated on various substrates was observed as a function of film thickness. The E_f of the conducting polymer surface was estimated by Kelvin probe method, and the Ip was estimated by atmospheric photoelectron spectroscopy. When Al was used as the electrode material, the dependence of the EF on film thickness was much different from that of the Ip. Less