Apertureless scanning near-field optical studies of energy and charge transfer in molecular materials for opto-electronic devices.

用于光电器件的分子材料中能量和电荷转移的无孔径扫描近场光学研究。

• 批准号: EP/E059716/1
• 负责人: Ashley Cadby
• 金额: $ 83.75万
• 依托单位: University of Sheffield
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2007
• 资助国家: 英国
• 起止时间: 2007 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FE059716%2F1
• 关键词: Apertureless; scanning; near; field; optical

The development of highly efficient electronic devices is a major goal of molecular electronics. To achieve this we need to fully understand how energy is passed from one molecule to another. Theoretically this is a simple problem to understand for two small molecules. However, in electronic devices made from blends of semi-conducting polymers energy transfer occurs at the boundaries between different polymer domains. At these boundaries many processes that occur on length scales of several nanometres can play an important role in the efficiency of the energy transfer process. To study the effect these processes have on device efficiency, I aim to develop an apertureless scanning near field microscope (A-SNOM). This microscope will allow me to study the optical properties of a variety of materials at a resolution high enough to resolve individual molecules.Using the A-SNOM I will study a variety of opto-electronic systems based on conjugated polymers. Firstly I will study blends of conjugated polymers. These polymers can be blended with other polymers or small molecules and be used as the active material in light emitting diodes or photo-voltaic devices. This will lead to a greater understanding of energy transfer in these systems and can be used to improve the efficiency of devices based on blends of conjugated polymers. The second group materials I will study will consist of light harvesting complexes (LHC) derived from specialised bacteria combined with conjugated polymers, in order that the polymers protect the bacteria while facilitating energy transfer from the polymer to the bacteria. This will represent one of the first nanoscale studies of the use of bacterial compounds in molecular electronics. Finally the A-SNOM will be used to study small numbers of interacting molecules. The high resolution of A-SNOM will allow me to image the optical properties of single molecules acting as either (energy) donor or acceptor molecules. This can be used to improve our understanding in the electronic interactions between these molecules. Studying single molecules (or two interacting molecules) will be of interest to theoreticians and will shed light on processes that occur in real devices. This is not possible using other conventional measurement techniques. Finally it will also be possible to directly correlate a molecules morphology with its energy transfer ability. The A-SNOM will allow me to make simultaneous measurements of a molecules morphology and optical properties. The results from these studies will be used in conjunction with a model photovoltaic device which will permit me to understand fundamental process which limit device performance. The device will consist of patterned strips of alternating low and high bang-gap polymers. It will be possible to incorporate results obtained during the studies outlined above to increase device efficiency.

开发高效电子器件是分子电子学的一个主要目标。为了实现这一目标，我们需要充分了解能量如何从一个分子传递到另一个分子。理论上，对于两个小分子来说，这是一个容易理解的简单问题。然而，在由半导体聚合物共混物制成的电子器件中，能量转移发生在不同聚合物域之间的边界处。在这些边界处，发生在几纳米长度尺度上的许多过程可以在能量转移过程的效率中发挥重要作用。为了研究这些过程对器件效率的影响，我的目标是开发一种无孔径扫描近场显微镜 (A-SNOM)。该显微镜使我能够以足够高的分辨率研究各种材料的光学特性，以解析单个分子。使用 A-SNOM，我将研究各种基于共轭聚合物的光电系统。首先，我将研究共轭聚合物的共混物。这些聚合物可以与其他聚合物或小分子共混，并用作发光二极管或光伏器件中的活性材料。这将有助于人们更好地了解这些系统中的能量转移，并可用于提高基于共轭聚合物共混物的设备的效率。我将研究的第二组材料将包括源自特殊细菌的光捕获复合物（LHC）与共轭聚合物的结合，以便聚合物保护细菌，同时促进能量从聚合物转移到细菌。这将代表在分子电子学中使用细菌化合物的首批纳米级研究之一。最后，A-SNOM 将用于研究少量相互作用的分子。 A-SNOM 的高分辨率将使我能够对充当（能量）供体或受体分子的单个分子的光学特性进行成像。这可以用来提高我们对这些分子之间电子相互作用的理解。研究单个分子（或两个相互作用的分子）将引起理论家的兴趣，并将揭示真实设备中发生的过程。使用其他传统测量技术这是不可能的。最后，还可以将分子形态与其能量转移能力直接关联起来。 A-SNOM 使我能够同时测量分子形态和光学特性。这些研究的结果将与模型光伏器件结合使用，这将使我能够了解限制器件性能的基本过程。该器件将由交替的低带隙和高带隙聚合物的图案条组成。可以将上述研究期间获得的结果结合起来以提高设备效率。