Investigations of the Relationship Between Molecular Structure and the Electronic Work Function in Metal Complex Thin Films

在化学系化学结构、动力学和机理计划和材料研究部固体材料化学计划的支持下，科罗拉多州立大学的C.Michael Elliott教授和他的研究小组将探索一系列零价金属-联吡啶络合物的分子结构与由这些络合物制备的薄膜的电子功函数之间的关系。基于联吡啶基团的配体可以很容易地进行修饰，这反过来又允许金属络合物的整体电子结构的可调性，并最终由这些络合物制成薄膜。薄膜的合成、光谱和电化学表征以及薄膜沉积程序的开发将在CSU的埃利奥特实验室进行。功函数测量将与怀俄明大学的布鲁斯·帕金森教授合作完成。这些金属络合物薄膜在发光设备和光伏方面的潜在应用将与国家可再生能源实验室的Brian Gregg博士合作进行研究。除了将获得的关于金属联吡啶体系的结构-性质关系的具体信息外，该研究项目还对发光二极管、光伏和其他基于分子的技术具有重要意义。除了上述通过化学结构修饰来调整材料性能的可能性外，金属联吡啶系统还提供了制备高质量薄膜的可能性，避免了目前低功函数金属薄膜所需的气相沉积过程带来的重大挑战(例如，高成本、有限的放大潜力等)。分子导体还提供了创建电子结的可能性，其中接触材料的化学兼容性比许多当前设备中的更好。最后，这项研究活动将为本科生和研究生的培训提供丰富的环境；他们不仅将获得基础化学和物理方面的专业知识，还将体验想法如何发展成新技术，从原子尺度到有形设备。

In this project supported by the Chemical Structure, Dynamics and Mechanisms Program of the Chemistry Division, and the Solid State Materials Chemistry Program of the Division of Materials Research, Professor C. Michael Elliott and his research group at Colorado State University will explore the relationships between molecular structure in a series zero-valent metal-bipyridyl complexes, and the electronic work function of films prepared from these complexes. Ligands based on the bipyridyl group can be easily modified, which in turn allows for tunability of the overall electronic structure of the metal complex, and ultimately the thin films made from these complexes. The synthesis, spectral and electrochemical characterizations, and development of thin film deposition procedures will be done in the Elliott laboratory at CSU. Work function measurements would be done in collaboration with Professor Bruce Parkinson of the University of Wyoming. The potential application of these metal complex films in light-emitting devices and photovoltaics will studied in collaboration with Dr. Brian Gregg at the National Renewable Energy Laboratory.In addition to the specific information to be obtained regarding the structure-property relationships in metal bipyridyl systems, this research project has significant implications for light emitting diode, photovoltaic and other molecularly-based technologies. In addition to the aforementioned possibility that material properties can be tuned via chemical structural modification, the metal bipyridyl systems offer the possibility that high quality thin films can be prepared avoiding important challenges posed by vapor deposition procedures currently required for low-work function metal films (e.g., high cost, limited scale-up potential, etc). Molecular conductors also offer the possibility of creating electronic junctions where the contacting materials are more chemically compatible than in many current devices. Finally, this research activity will serve as a rich environment for the training of undergraduate and graduate students; they will not only gain expertise in fundamental chemistry and physics, but also experience how ideas develop into new technologies, literally from the atomic scale to the tangible device.