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.

发展高效的电子器件是分子电子学的一个主要目标。要做到这一点，我们需要完全理解能量是如何从一个分子传递到另一个分子的。从理论上讲，对于两个小分子来说，这是一个很容易理解的问题。然而，在由半导电聚合物的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。在这些边界上，许多发生在几纳米长度尺度上的过程可以在能量转移过程的效率中发挥重要作用。为了研究这些工艺对器件效率的影响，我的目标是开发一种无孔径扫描近场显微镜（A-SNOM）。这台显微镜将使我能够研究各种材料的光学性质，分辨率高到足以分辨单个分子。使用A-SNOM，我将研究基于共轭聚合物的各种光电系统。首先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。这将导致对这些系统中的能量转移有更好的理解，并可用于提高基于共轭聚合物共混物的器件的效率。我将研究的第二组材料将由来自特定细菌的光捕获复合物（LHC）与共轭聚合物结合组成，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作为（能量）供体或受体分子的单个分子的光学性质进行成像。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。研究单分子（或两个相互作用的分子）将是理论家感兴趣的，并将揭示在真实的设备中发生的过程。这是不可能使用其他传统的测量技术。最后，还可以将分子形态与其能量传递能力直接关联。A-SNOM将允许我同时测量分子形态和光学性质。这些研究的结果将与模型光伏器件结合使用，这将使我能够理解限制器件性能的基本过程。该器件将由交替的低和高带隙聚合物的图案化条带组成。将有可能纳入上述研究期间获得的结果，以提高器械效率。