CAREER: Freeze-frame Spectroscopy, a technique for elucidation of fundamental interactions underlying nanocatalytic reactions

这项由化学系化学催化计划颁发的职业奖项支持利哈伊大学的David T.Moore教授开发冻结帧光谱(FFS)的工作，FFS是一种直接探测反应物分子与纳米催化剂相互作用的实验方法。冷冻框架光谱学被明确地设计用来稳定低温基质中感兴趣的预反应络合物，以便可以使用振动光谱学对它们进行结构表征。这种矩阵隔离光谱技术提供的高分辨率允许检测与反应物分子和催化剂材料的相互作用相关的振动带中的特征位移。FFS方法还探索了纳米催化反应途径。共振激光泵浦被用来快速地将能量沉积到稳定的预反应复合体中，以便它们能够跨越激活势垒形成反应性中间体或产物复合体，然后被捕获和表征。摩尔教授的研究重点是金纳米颗粒上的一氧化碳(CO)氧化，以便更好地了解纳米颗粒大小和电荷的趋势如何与反应性的趋势相关联。激光泵浦实验在荷兰Nieuwegein的自由电子激光设施(Felix)进行，以验证检测到的络合物的反应前性质，并进一步表征催化反应路径的势能面。与南山学院建立了一项新的合作伙伴关系，为非理科专业的学生提供身临其境的科学研究学习体验。这项由化学系化学催化项目颁发的职业奖项支持利哈伊大学的大卫·T·摩尔教授开发冻结帧光谱学(FFS)，这是一种研究反应物分子和纳米催化剂之间相互作用的实验方法。催化剂是用来加快化学反应速度的。直接检查反应物-催化剂络合物是不可能的，因为好的催化剂不会将反应物结合得很强或很长时间。FFS克服了这一障碍，它使用非常低的温度来减缓催化反应，然后利用光来拍摄反应物-催化剂相互作用的快照。在荷兰进行的其他激光研究对FFS实验进行了验证。摩尔教授的研究生前往Nieuwegein进行这些测量并获得对国际文化的欣赏。最初的研究考察了金纳米颗粒上的氧(O2)对一氧化碳(CO)的催化氧化。这一反应在替代能源领域具有重要意义，因为CO对氢燃料电池中使用的催化剂是一种强烈的毒害。这项工作的更广泛影响包括开发在文科课程范围内向人文和社会科学专业教授科学的新方法。教师将与学生一起开发与学生主要感兴趣的领域相关的简短、专注的研究项目。这些项目为本科生提供了对科学方法的重要方面的洞察。

This CAREER award by the Chemical Catalysis Program of the Chemistry Division supports the work of Professor David T. Moore of Lehigh University to develop freeze-frame spectroscopy (FFS), an experimental method to directly probe interactions of reactant molecules with nanocatalysts. Freeze-frame spectroscopy is explicitly designed to stabilize the pre-reactive complexes of interest in cryogenic matrices so that they may be structurally characterized using vibrational spectroscopy. The high-resolution afforded by this matrix-isolated spectroscopic technique allows detection of the characteristic shifts in vibrational bands associated with the interaction of the reactant molecules and the catalyst material. The FFS approach also explores nanocatalytic reaction pathways. Resonant laser pumping is used to rapidly deposit energy into the stabilized pre-reactive complexes so that they can cross activation barriers to form reactive intermediates or product complexes that are then trapped and characterized. Professor Moore's research focuses on carbon monoxide (CO) oxidation on gold nanoparticles in order to better understand how trends in nanoparticles size and charge correlate to trends in reactivity. Laser pumping experiments are carried out at the free-electron laser facility (FELIX) in Nieuwegein, Netherlands, in order to verify the pre-reactive nature of the detected complexes and to further characterize the potential energy surfaces of the catalytic reaction pathways. A new partnership with South Mountain College has been developed to provide immersive learning experiences in scientific research to non-science majors.This CAREER award by the Chemical Catalysis Program of the Chemistry Division supports the work of Professor David T. Moore of Lehigh University to develop freeze-frame spectroscopy (FFS), an experimental method which looks at interactions between reactant molecules and nanometer-sized catalysts. Catalysts are used to increase the speed of chemical reactions. Direct examinations of reactant-catalyst complexes are rarely possible because good catalysts do not bind reactants very strongly or for very long. FFS overcomes this hurdle by using very low temperatures to slow the catalytic reactions and then employing light to take a "snapshot" of the reactant-catalyst interaction. The FFS experiments are verified by additional laser studies conducted in the Netherlands. Professor Moore's graduate students travel to Nieuwegein to perform these measurements and to gain an appreciation for international culture. Initials studies examine the catalytic oxidation of carbon monoxide (CO) by oxygen (O2) on gold nanoparticles. This reaction has relevance in the alternative energy arena, since CO is a potent poison for the catalysts used in hydrogen fuel cells. The broader impacts of this work include the development of new methods for teaching science to humanities and social science majors within the liberal arts curriculum. Instructors will work with students to develop short, focused research projects with relevance to the students' primary areas of interest. These projects provide the undergraduates with insight into vital aspects of the scientific method.