RUI: Support Shape Effect in Metal-CeO2 Catalysis on Low-Temperature CO Oxidation

扬斯敦州立大学的王瑞刚教授由化学系的化学催化项目资助，用于帮助改善用于催化危险的一氧化碳排放转化为危害较小的物质的系统的性能。这些催化转化系统由负载在金属氧化物基底上的微小金属颗粒组成，用于汽车中作为排气净化系统的一部分，但也可用于气体传感器，燃料电池和其他有用的设备。小金属颗粒与氧化物基质的相互作用的性质，以及系统的这两个部分之间的接触面积，决定了催化剂的选择性和活性。因此，本研究的目标是更深入，更详细地了解金属颗粒和氧化物衬底之间的接触如何影响催化，以便提高这些器件的性能。除了这项工作对社会使用技术产生更广泛的影响外，这项工作还积极影响了参与研究的一些本科生的教育经验。扬斯敦州立大学招收的学生中有很高比例来自传统上在科学领域代表性不足的群体，因此研究团队正在与该大学的其他项目合作，让这些少数群体的学生参与该项目。该研究通过将来自周边地区的社区大学教师纳入研究团队而产生了进一步的影响。该项目的重点是阐明氧化铈（CeO 2）载体的形状和大小对一氧化碳氧化的影响。目标是开发在低温下具有高氧化还原活性的稳定催化剂。颗粒形状，特别是暴露在微晶表面上的晶面类型被认为在铈基氧化物型氧化还原催化剂的表面还原性和催化活性中起主要作用。在初步研究中获得的初步数据表明，CeO 2颗粒形状为具有反应性{110}、{100}、{211}等的纳米棒、纳米管或纳米立方体，晶体表面上的面可以使用水热法和微波法产生。在该项目中，研究小组正在制备具有明确尺寸和形状的CeO 2载体，并研究这些形状和尺寸如何影响模型催化反应，如一氧化碳氧化和水煤气变换反应。本研究的总体目标是开发一种预测模型，该模型自然地将不同的金属与各种CeO 2表面联系起来，以获得上级低温催化活性。通过开发这种预测模型，该项目有可能对催化、燃料反应和气体传感等许多实际应用的材料加工产生重大影响，其中铈基氧化物的氧化还原功能起着至关重要的作用。

Professor Ruigang Wang of Youngstown State University is funded by the Chemical Catalysis Program of the Division of Chemistry for research to help improve the performance of systems used to catalyze the conversion of dangerous carbon monoxide emissions to less harmful substances. These catalytic conversion systems, composed of tiny particles of metal supported on a metal oxide substrate, are used in automobiles as part of the exhaust clean-up system, but also find application in gas sensors, fuel cells and other useful devices. The nature of the interaction of the small metal particles with the oxide substrate, as well as the contact area between these two parts of the system, determines how selective and active the catalytic convertor is. Therefore, the goal of this research is to develop a deeper and more detailed understanding of how contact between the metal particles and the oxide substrate affects the catalysis so that performance of these devices can be improved. In addition to the broader impact that this work is having on technology of use to society, the work is also positively affecting the educational experience of a number of undergraduate students involved in the research. Youngstown State enrolls a high percentage of students from groups that are traditionally under-represented in science, so the research team is working with other programs at the university to engage students from these minority groups in the project. The research is having a further impact by the inclusion of community college faculty from the surrounding region in the research team.This project focuses on elucidating the effect of the shape and size of cerium oxide (CeO2,) supports on carbon monoxide oxidation. The goal is to develop stable catalysts with high redox activity at low temperatures. Particle shape and, especially, the type of crystalline faces exposed on the surface of crystalites are believed to play a major role in surface reducibility and catalytic activity of cerium-based oxide type redox catalysts. Preliminary data obtained in a pilot study have shown that CeO2 particles shaped as nanorods, nanotubes, or nanocubes with reactive {110}, {100}, {211}, etc., faces on the crystal surface can be produced using hydrothermal and microwave methods. In this project, the research team is preparing CeO2 supports with well-defined sizes and shapes, and investigating how these shapes and sizes affect model catalytic reactions, such as carbon monoxide oxidation and the water-gas shift reaction. The overall goal of this research is to develop a predictive model that naturally links different metals with various CeO2 surfaces for a superior low-temperature catalytic activity. Through the development of such a predictive model, the project has the potential to have a major impact on materials processing for many practical applications such as catalysis, fuel reaction and gas sensing, where the redox functionality of cerium-based oxides plays a crucial role.