Building Electron Transfer Cascades into Amphiphlic Donor-Acceptor Assemblies

将电子转移级联构建成两亲性供体-受体组件

• 批准号: 1608957
• 负责人: Sarah Tolbert
• 金额: $ 69.98万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2020-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1608957&HistoricalAwards=false
• 关键词: Building; Electron; Transfer; Cascades; into

In this project funded by the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Professors Sarah Tolbert, Benjamin Schwartz, and Yves Rubin of the Department of Chemistry at the University of California, Los Angeles are developing complex molecules that will convert light into separated electrical charges that can drive useful chemical reactions. In natural systems, such as photosynthesis, the absorption of light energy can be translated efficiently into separated electrical charges. These charges can then be used to conduct a range of important chemical reactions, and the overall process is called photochemistry. Using modern synthetic chemistry, Professors Tolbert, Schwartz and Rubin are creating molecules that absorb light efficiently and then separate the electrical charges via a series of cascades across the molecules. Then, they are examining ways to use those separated charges to do useful chemistry. In the process, they are training a group of graduate students in interdisciplinary science. Those students are further working to share their knowledge of photochemistry and photochemical technologies with a broad range of middle and high school students in the greater Los Angeles area. Professors Tolbert, Schwartz and Rubin are studying ways to create and exploit artificial electron transfer cascades using strongly absorbing pi-conjugated polymers and molecules. The principal challenges in producing artificial electron transfer cascades are first to create well-defined donor/acceptor pairs and second to place additional acceptors with progressively lower LUMOs at precise positions so that their energy gradient leads to spatial separation of the initially created charge pair. The cascades are being constructed starting with amphiphilic, water-soluble pi-conjugated polymers that assemble into networks of electrically-interconnected micelles. The conjugated polyelectrolytes are then assembled with charged C60 derivatives or other pi-conjugated acceptors. The structure of the assembly and the energetics of both the polymer donor and the pi-conjugated electron acceptor are being tuned. The electron transfer cascades are being characterized using ultrafast transient absorption spectroscopy, and the structures are being correlated with the observed photochemical properties. Optimized assemblies are being adapted for use as photosensitizers in reduction reactions.

在这个项目中，由化学系的大分子，超分子和纳米化学计划资助，洛杉矶大学化学系的莎拉·托尔伯特（Sarah Tolbert），本杰明·施瓦茨（Benjamin Schwartz）和伊夫·鲁宾（Yves Rubin），洛杉矶大学，洛杉矶分子正在开发复杂的分子，这些复杂分子会开发出光线，这些分子将转化为可驱动有用化学化学反应的分离的电荷。 在诸如光合作用之类的天然系统中，光能的吸收可以有效地转化为分离的电荷。 然后，这些电荷可用于进行一系列重要的化学反应，总体过程称为光化学。 使用现代的合成化学，Tolbert，Schwartz和Rubin教授正在创建有效吸收光的分子，然后通过一系列跨分子的级联反应分离电荷。 然后，他们正在研究使用那些分开的费用来进行有用的化学反应的方法。 在此过程中，他们正在培训一群跨学科科学的研究生。这些学生正在进一步努力与大洛杉矶地区的广泛中学学生分享他们对光化学和光化学技术的了解。 Tolbert，Schwartz和Rubin教授正在研究使用强烈吸收的Pi偶联的聚合物和分子来创建和利用人工电子转移级联的方法。产生人工电子传输级联的主要挑战首先是创建定义明确的供体/受体对，其次是将额外的受体放置在精确的位置逐渐较低的Lumos，以便它们的能量梯度会导致最初创建的电荷对的空间分离。 从两亲性的，水溶性的PI偶联的聚合物开始，将级联反应构建，这些聚合物聚集到电连接的胶束网络中。然后将共轭聚电解质与带电的C60衍生物或其他PI结合的受体组装在一起。 聚合物供体和PI偶联电子受体的组件和能量的结构正在调节。 通过超快瞬态吸收光谱法表征了电子传输级联，并且结构与观察到的光化学特性相关。 优化的组件正在调整以作为光敏剂在还原反应中用作光敏剂。