SusChEM: Studying Catalysts and Reaction Intermediates for Water Oxidation by Spectroscopy of Cryogenic Mass-Selected Ions

SusChEM：通过低温质量选择离子光谱研究水氧化的催化剂和反应中间体

• 批准号: 1361814
• 负责人: J Mathias Weber
• 金额: $ 42.69万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1361814&HistoricalAwards=false
• 关键词: SusChEM; Studying; Catalysts; Reaction; Intermediates

With this award from the Chemical Structure, Dynamics and Mechanisms A program, Mathias Weber of the University of Colorado at Boulder develops a new experimental approach to study chemical reactions that occur in a solar energy conversion reactor. The type of reactor being studied utilizes a catalyst molecule that contains either ruthenium or copper to split water molecules into hydrogen and oxygen. Energy from sunlight is, thus, used to extract a sustainable source of fuel from water, but the precise way it works is not fully understood. This lack of understanding hinders the design and improvement of catalysts and reactors for this important technological process. One of the complicating factors in studies of this system is the presence of the water itself. The current research is getting around this problem by removing the molecules produced in the solar reactor and putting them into a vacuum. Highly sophisticated pieces of equipment can then be used to study the detailed nature of these chemical species. The measurements made in vacuum will then provide signatures that can be used later to identify those species when water is present, in other words, in the reactor as it normally functions. The work addresses an important societal problem, the development of alternative sources of energy that do not rely on carbon-based fuels. Training the next generation of scientists is an integral part of this project. It includes budding researchers as young as grades five through nine through a Saturday morning science program.In this project, the investigators are studying the electronic and geometric structures of selected ruthenium- and copper-based catalysts for water oxidation, as well as certain reaction intermediates that arise in the catalytic conversion process. Ions of catalyst and reaction intermediates are transferred into the gas phase by electrospray ionization. The ions are then cooled in an ion trap, mass selected, and irradiated by pulsed light, which is tunable throughout the mid-IR, visible and near-UV spectrum. Photon absorption is monitored by photofragmentation of the target ions, allowing the measurement of their vibrational and electronic spectra. Cooling the ions to low temperatures is crucial to obtain the necessary spectroscopic detail. Vibrational spectra will result in structural information about the ions under study, which is particularly important for reaction intermediates. Measuring the electronic spectra of catalysts and reaction intermediates will aid clarification of speciation in reactive solutions. In addition, the excited state vibrational structure is assisting the investigators in computational modeling studies of the excited state dynamics and reactivity.

通过化学结构，动力学和机制的奖项，科罗拉多大学博尔德分校的Mathias Weber开发了一种新的实验方法来研究太阳能转化反应器中发生的化学反应。所研究的反应器的类型利用含有氟芬氏菌或铜的催化剂分子将水分子分成氢和氧。因此，来自阳光的能量是用来从水中提取燃料的可持续燃料来源的，但是确切的工作方式尚未完全理解。缺乏理解阻碍了这一重要技术过程的催化剂和反应堆的设计和改进。该系统研究中的复杂因素之一是水本身的存在。当前的研究是通过去除太阳能反应器中产生的分子并将其放入真空中来解决这个问题。然后可以使用高度复杂的设备来研究这些化学物种的详细性质。然后，真空中进行的测量将提供签名，以后可以使用这些签名，以便在反应堆中在反应堆中正常起作用时在存在水时识别这些物种。这项工作解决了一个重要的社会问题，即不依赖碳燃料的替代能源的发展。培训下一代科学家是该项目不可或缺的一部分。它包括年轻的研究人员，年龄在五年级至九年级到星期六早上的科学计划。在该项目中，研究人员正在研究选定的氟芬氏菌和基于铜的催化剂的电子和几何结构，用于水氧化，以及某些反应中间体这是在催化转化过程中产生的。通过电喷雾电离将催化剂和反应中间体的离子转移到气相中。然后将离子在离子陷阱中冷却，质量选择并被脉冲光照射，脉冲光在整个IR中可调，可见且近紫外的光谱。通过靶离子的光碎片来监测光子的吸收，从而可以测量其振动和电子光谱。 将离子冷却至低温对于获得必要的光谱细节至关重要。振动光谱将导致有关正在研究的离子的结构信息，这对于反应中间体特别重要。测量催化剂和反应中间体的电子光谱将有助于阐明反应溶液中的物种。此外，激发的状态振动结构正在帮助研究者参与激发态动力学和反应性的计算建模研究。