RUI: Mechanistic Investigation of Photochemical Products from Iron-Iron Hydrogenase Model Compounds; Insight into the Catalytic Generation and Activation of Molecular Hydrogen

卡门教授在化学系化学催化(CAT)计划的支持下，在索诺马州立大学进行研究，以阐明铁-铁氢酶模型化合物的机理。铁-铁氢酶是一种催化分子氢可逆氧化的有机金属酶。化石燃料的使用对我们的全球生态系统的有害影响，以及不断增长的能源需求，促使人们对开发清洁和可再生燃料进行了大量研究。氢被视为理想的无碳能源，因为它唯一的燃烧产物是水。不幸的是，最好的氢气产生和使用催化剂是基于稀有和非常昂贵的铂金属，这给大规模生产氢气以满足我们的能源需求带来了巨大的经济障碍。然而，大自然提供了高效而强大的富含地球的金属酶，能够清洁地产生氢气。由于这一自然过程的潜在重要性和实用性，目前的工作重点是了解这些酶中发生的催化化学，以促进设计新的、廉价的氢气利用技术体系。这个项目的方法是制造作为酶活性中心的结构和功能模型的金属有机小分子，并使用光谱和动力学技术来表征它们的光化学反应和热反应活性。工作假设是光在溶液中产生活性催化剂。这项工作正在导致对基本反应性的更深层次的理解。这一建议中使用的策略是合成一系列分子，这些分子在电子和空间性质上都不同，但具有一般的双铁核，并研究在CO和H2下的光化学。此外，正在研究光产物与氢的热反应性作为溶剂的函数，以了解催化作用。实验结果与理论计算结果进行了比较。此外，该项目具有很大的教育影响，正在提供无机合成、光谱学、催化、光化学领域的培训，并使本科生接触理论化学。特别是通过在区域和国家会议和出版物上的发言，向科学界和当地社区进行宣传，包括本科生。

Professor Carmen Works is supported by the Chemical Catalysis (CAT) Program in the Division of Chemistry to conduct research at Sonoma State University to elucidate the mechanism of iron-iron hydrogenase model compounds. Iron-iron hydrogenase is an organometallic enzyme that catalyzes the reversible oxidation of molecular hydrogen. The detrimental effects of fossil fuel usage on our global ecosystem as well as ever increasing energy demands have inspired much research towards the development of clean and renewable fuels. Hydrogen is seen as an ideal carbon-free energy source as its only combustion product is water. Unfortunately, the best catalysts for hydrogen generation and usage are based on the rare and very expensive platinum metal, presenting a significant economic obstacle for the large-scale production of hydrogen to meet our energy demands. However, Nature has provided efficient and robust Earth rich metal enzymes, that are able to produce hydrogen cleanly. Due to the potential importance and utility of this natural process, the present work is focused on understanding the catalytic chemistry that occurs in these enzymes in order to advance the design of new and inexpensive technological systems for hydrogen use. The approach in this project is to make small organometallic molecules that are both structural and functional models of the enzyme active site and to use spectroscopic and kinetic techniques to characterize their photochemical and thermal reactivity. The working hypothesis is that light produces the active catalysts in solution. This work is leading to a deeper understanding of the fundamental reactivity. The strategy used in this proposal is to synthesize a range of molecules that vary in both electronic and steric properties but have the general di-iron core, and to study the photochemistry under CO and H2. In addition, the thermal reactivity of the photoproducts with hydrogen as a function of solvent is being studied to understand catalysis. Experimental results are being compared with theoretical calculations. In addition, this project has a large educational impact and is providing training in the area of inorganic synthesis, spectroscopy, catalysis, photochemistry and exposed undergraduate students to theoretical chemistry. Outreach to both the scientific and local community is including undergraduate students specifically through presentations at regional and National meetings and publications.