Design rules for synthesis of stable single-site catalysts from experiment and first principles theory

在NSF化学部化学催化计划的资助下，宾夕法尼亚州立大学的Rioux和Janik博士正在开发提供新的、更有效的催化剂的基本原理。目前使用的大多数催化剂由载体材料上的金属原子聚集体组成。金属通常稀有且昂贵，并且聚集体内的金属原子在催化中没有活性。如果这些昂贵的金属在载体上以单个原子而不是聚集体的形式使用，则可以更有效地使用它们。因此，存在制备单原子金属催化剂的显著动机。 宾夕法尼亚州立大学的研究小组正在使用实验和计算方法相结合的方法来确定和理解可以成功制备单原子催化剂的条件。来自科学和工程学代表性不足群体的本科生正在参与这些研究工作。此外，学生研究人员正在开发教学模块，展示能源生产如何影响我们的环境，以纳入针对学生和公众的外联活动。单原子催化剂代表了一种令人兴奋的新型催化剂，在能源生产相关的化学反应中表现出高活性。 Robert Rioux博士和Michael Janik博士的研究小组正在开发计算推导和实验验证的设计规则，用于稳定可还原氧化物上的单原子图案。 该合成方法是基于贵金属前体的强静电吸附，其将限定氧化物载体上的金属负载的上限。 计算和实验技术的结合允许确定描述符，这些描述符指导用于合成稳定的贵金属单原子催化剂的前体、载体和pH的选择。 等温滴定量热法测量的吸附在固-液界面和密度泛函理论计算正在被用来评估和预测的条件，导致形成稳定的单原子催化剂。 由于其作为低温甲烷氧化催化剂的前景，二氧化铈上的Pd系统被用作初始试验台。 该研究项目包括通过少数民族本科生研究经验和妇女参与科学和工程研究计划，该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响进行评估，被认为值得支持审查标准。

With funding from the Chemical Catalysis Program of the NSF Division of Chemistry, Drs. Rioux and Janik of Penn State University are developing fundamental principles to provide new, more effective catalysts. Most catalysts used today consist of aggregates of metal atoms on a support material. The metals are often rare and expensive, and the metal atoms inside the aggregates are not active in catalysis. Much more efficient use of these expensive metals is possible if they are used as single atoms, and not aggregates, on the support. Thus, there is significant motivation for preparing single atom metal catalysts. The Penn State team is using a combination of experimental and computational methods to determine and understand the conditions under which single atom catalysts can be successfully prepared. Undergraduates from groups underrepresented in science and engineering are being included in these research efforts. In addition, student researchers are developing teaching modules that demonstrate how energy production impacts our environment for inclusion in outreach activities directed at students and the general public.Single-atom catalysts represent an exciting new class of catalysts that have demonstrated high activity for chemical reactions relevant in energy production. The research groups of Dr. Robert Rioux and Dr. Michael Janik are developing computationally derived and experimentally validated design rules for the stabilization of single-atom motifs on reducible oxides. The synthesis approach is based on the strong electrostatic adsorption of precious group metal precursors that will define the upper boundary for metal loading on oxide supports. The combination of computational and experimental techniques is allowing the determination of descriptors that guide the choice of precursors, support, and pH for the synthesis of stable precious metal single atom catalysts. Isothermal titration calorimetry measurements of adsorption at the solid-liquid interface and density functional theory calculations are being used to evaluate and predict conditions leading to formation of stable single atom catalysts. The Pd on ceria system is being used as an initial testbed due to its promise as a low-temperature methane oxidation catalyst. The research project includes undergraduate involvement in research through the Minority Undergraduate Research Experience and Women in Science and Engineering Research programs, and is generating teaching modules that demonstrate the impact of energy production on our environment for use in outreach activities.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.