Development and Study of Hybrid Organic-Colloidal Quantum Dot Systems

碳基材料（有机或聚合物材料）由于其广泛的性质和制造低成本器件的潜力而引起研究人员和工业界的极大兴趣。近年来，对这些类型的材料的深入研究已经导致它们在电子器件中的使用，例如用于显示应用的发光二极管。这项研究已被证明是特别成功的，这些设备现在已经在许多商业应用中发现。在这项工作取得成功之后，研究人员将注意力转向将这些材料用于发射近红外（NIR）光的设备和太阳能电池中。由于许多限制因素，这项研究迄今为止还未能证明这些类型的设备以足够高的效率运行。限制因素基于这些材料的基本性质，包括导致光发射的过程以及允许能量和电荷在材料之间和材料内移动的机制。最近，已经开发出一类新的非碳基（无机）粒子，其行为类似于称为量子点（QD）的人造原子。这些QD具有许多对于在诸如上述那些装置中使用感兴趣的性质。特别地，如果适当地激发，QD可以被设计和调谐为有效地发射从光谱的可见光到红外区域的光。这些量子点也可以被隔离并涂覆有有机材料，从而允许它们用于将有机和无机材料混合在一起的混合系统中。这样的混合系统具有生产新一代高效装置的巨大潜力，所述高效装置包括太阳能电池和红外发射器，所述装置的生产效率高且成本低。然而，迄今为止报道的所有设备（基于这种混合材料）都表现出的效率远低于系统设计更好时可能达到的效率。为了设计这样的“优化系统”，必须充分了解有机和无机材料之间的相互作用，这样我们才能利用发生的机制对我们有利。在这个计划中进行的研究旨在更清楚地了解这些混合系统中有机和无机材料（分别为有机分子和量子点）之间的相互作用和相关机制。将使用的技术包括使用飞秒光谱技术与其他更标准的技术一起沿着实时研究这些过程。通过改变所使用的有机分子和量子点，将获得许多代表性系统的详细测量。所获得的实验数据将用于制定一个重要的过程，管理这些系统中的相互作用的理解，以及如何将其与当前的模型。获得这种理解后，它将用于设计和优化新的混合动力系统，提高应用的效率。我们将使用这些“优化的混合系统”来展示近红外中的光和电激发发射，其效率高于目前最先进的设备。同样，我们也将努力展示一种效率显著提高的太阳能电池。其中一个目标是与韩国领先的化学家建立国际合作，这将有利于每个机构和每个国家更广泛的研究界开展的研究。在这项合作中，化学家将提供量子点，旨在发射近红外涂层在一些不同的有机络合物（配体）。第二个目标是建立一个由申请人领导的公认的研究小组，在器件应用的功能有机和杂化材料的开发和研究方面开展领先的工作。

Carbon-based materials (organic or polymer materials) are of great interest to researchers and industry due to their wide ranging properties and potential to fabricate low-cost devices from them. In recent years intensive research into these types of materials has lead to their use in electrical devices such as light emitting diodes for display applications. This research has proved particularly successful and these devices are now found in a number of commercial applications. Following the success of this work researchers have turned their attention to using these materials in devices that emit near infra-red (NIR) light, and in solar cells. Due to a number of limiting factors, this research has not to date been able to demonstrate these types of devices operating with a high enough efficiency. The limiting factors are based on the fundamental properties of these materials and include the processes that lead to light being emitted and the mechanisms that allow energy and charge to move between and within the materials.Recently, a new class of non-carbon based (inorganic) particles have been developed that behave like artificial atoms called quantum dots (QDs). These QDs have a number of properties that are of interest for use in devices such as those mentioned above. In particular, QDs can be designed and tuned to emit light efficiently from the visible into the infra-red region of the spectrum if suitably excited. These QDs can also be isolated and coated with organic materials thus allowing them to be used in hybrid systems that mix organic and inorganic materials together. Such hybrid systems have great potential for producing a new generation of efficient devices including solar cells and infra-red emitters that are highly efficient and low cost to produce. However, all of the devices reported to date (that are based on this hybrid mixture of materials) have exhibited efficiencies well below what could be possible if the systems were better designed. In order to design such 'optimised systems' the interactions between the organic and inorganic materials must be fully understood so we can utilise the mechanisms taking place to our favour.The research to be carried out in this programme is designed to obtain a clearer understanding of the interactions and associated mechanisms that take place between the organic and inorganic materials (organic molecules and QDs respectively) in these hybrid systems. The techniques that will be used include studying these processes in real-time using femtosecond spectroscopy techniques along with other more standard techniques. By varying the organic molecules and QDs used, detailed measurements of a number of representative systems will be obtained. The experimental data obtained will be used to formulate an understanding of the significant processes that govern the interactions in these systems, and how this relates to current models. Having obtained this understanding it will be used to design and optimise new hybrid systems with improved efficiency for the applications in mind. We will use these 'optimised hybrid systems' to demonstrate optically and electrically excited emission in the NIR with improved efficiency over currently state-of-the-art devices. Similarly, we will also seek to demonstrate a solar cell with significantly improved efficiency.There are two further aims of this research. One of these aims is to establish an international collaboration with leading chemists in Korea that will benefit the research carried out at each institution and the wider research community in each country. In this collaboration the chemists will provide QDs designed to emit in the NIR coated in a number of different organic complexes (ligands). The second aim is to establish a recognised research group led by the applicant carrying out leading work on the development and study of functional organic and hybrid materials for device applications.