Synthesis and Physico-Chemical Characterization of Molecular Optoelectronic Gates

这个授予北卡罗来纳州立大学乔纳森·S·林赛的新合作团体奖得到了化学部的先进材料计划、材料研究部的电子材料计划以及数学和物理科学局的多学科活动办公室的支持。这项合作是由加州大学河滨分校的林赛和大卫·F·博西安以及华盛顿大学的杜威·霍尔滕共同完成的。合作者的专业知识涵盖分子电子系统的合成、静态表征和动态光物理研究。本论文的研究重点是基于多卟啉阵列的分子光电子门的设计、合成和物理表征。门是分子线的概念延伸，可以通过放置镁卟啉部分来开启或关闭信号传输，该部分通过化学、电化学或光化学氧化打开一个通道，将激发态能量输送到基态。这些氧化还原驱动的分子门与晶体管开关的操作平行。将研究门控现象的范围、光学门控的方法，以及结合分子门实现逻辑功能。静态和瞬时吸收和荧光光谱、共振拉曼光谱和电化学将被用来表征溶液中和薄膜中的体系。将在新阵列上进行时间分辨吸收和荧光测量，以阐明能量和电子转移的速率和路径。这项研究解决的根本问题是，分子电子学是否是推动计算机小型化的可行极限，以及是否有可能在分子水平上进行信息处理。即将研制的分子光电子门将模拟传统电路中的固态晶体管。如果成功，分子光电子门可能会被用作传感器或其他智能结构的组件。

This new collaborative group award to Jonathan S. Lindsey at North Carolina State University is supported by the Advanced Materials Program in the Chemistry Division, the Electronic Materials Program in the Division of Materials Research and the Office of Multidisciplinary Activities in the Mathematical and Physical Sciences Directorate. The collaboration is between Lindsey and David F. Bocian at the University of California at Riverside and Dewey Holten at Washington University. The expertise of the collaborators spans synthesis, static characterization and dynamic photophysical studies of molecular electronic systems. The focus of the research is the design, synthesis and physical characterization of molecular optoelectronic gates based on multi-porphyrin arrays. The gates are conceptual extensions of molecular wires where the signal transmission can be turned on or off by placement of a magnesium porphyrin moiety which by chemical, electrochemical, or photochemical oxidation opens a channel that funnels excited-state energy to the ground state. These redox-driven molecular gates parallel the operation of transistor switches. The scope of the gating phenomenon, optical gating methods, and and the combination of molecular gates to achieve logic functions will be studied. Static and transient absorption and fluorescence spectroscopy, resonance Raman spectroscopy and electrochemistry will be used to characterize the systems both in solution and as thin films. Time-resolved absorption and fluorescence measurements will be made on the new arrays to elucidate the rates and pathways of energy and electron transfer. This research addresses the fundamental issue of whether molecular electronics are a viable limit in the drive towards computer miniaturization and whether information processing is possible at the molecular scale. The molecular optoelectronic gates which will be prepared will simulate the solid-state transistors in conventional circuitry. If successful, molecular optoelectronic gates may find applications as sensors or as components of other smart structures.