Collaborative Research: Correlating Molecular Structure and Activity in Boron-containing ODH Catalysts

随着世界人口的增长，对消费品的需求也在增加，消费品是由乙烯和丙烯等基本化学品制成的。该项目的重点是发现节能催化剂，用于从天然气中生产这些化学构件，同时最大限度地减少二氧化碳等不良副产品的产生。 研究人员的初步研究表明，含硼催化剂具有特殊的前景，但需要更深入的原子级理解才能进一步提高催化剂的性能和耐久性。 该项目将利用新的催化剂合成方案，最先进的固态核磁共振成像和计算方法的组合来获得所需的原子级理解，并利用这种见解来设计改进的催化剂。 该研究将通过其将我国巨大的页岩气资源有效转化为增值燃料和化学品的潜力来支持美国的清洁能源安全。低碳烷烃的氧化脱氢（ODH）是生产重要化学结构单元的一种有前途的替代方法。然而，尽管经过数十年的研究，高选择性催化剂仍然难以捉摸，因为过氧化是一种容易且在化学上有利的过程。首席研究员小组最近的研究表明，含硼催化剂（hBN、BNNT、WB等）是轻质烷烃ODH的高选择性催化剂。对于丙烷ODH，与现有技术的基于氧化钒的催化剂在10%丙烷转化率下的60%丙烯选择性相比，在高达20%转化率下可以获得高达80%的丙烯选择性。鉴于最近发现这类材料作为ODH催化剂，有许多基本问题需要回答的活性位点和它们的形成。控制合成，最先进的固态NMR（SSNMR）光谱和计算建模将被用来深入了解催化活性位点，并建立含硼ODH催化剂的结构-性能关系。这项工作将有助于从分子水平上理解一个具有工业重要性的复杂问题。我们的多学科方法包括合成，SSNMR表征，催化测试和计算建模将训练参与的学生使用来自各个领域的信息来开发复杂系统的详细图片。此外，这项工作的协作性质将帮助学生成长为一个研究团队的生产成员。除了有针对性的反应，这项研究将是有价值的更广泛的催化社区，因为广义的催化见解和方法开发的表征异质材料。这个奖项反映了NSF的法定使命，并已被认为是值得的支持，通过评估使用基金会的知识价值和更广泛的影响审查标准。

As the world population grows, the demand for consumer goods, which are made from building-block chemicals such as ethylene and propylene, increases. The project focuses on discovery of energy-efficient catalysts for the production of these chemical building-blocks from natural gas with minimal generation of undesired by-products such as carbon dioxide. Preliminary studies by the investigators have shown exceptional promise of boron-containing catalysts, but deeper, atomic-level understanding is needed to further improve the catalyst performance and durability. The project will utilize a combination of new catalyst synthesis protocols, state-of-the-art solid-state nuclear magnetic resonance imaging, and computational methods to obtain the needed atomic-level understanding, and use that insight to design improved catalysts. The research will support U.S. clean-energy security through its potential for the efficient conversion of our nation's vast shale gas resources to value-added fuels and chemicals. Oxidative Dehydrogenation (ODH) of light alkanes is a promising alternative for the production of important chemical building blocks. However, despite decades of research, a highly selective catalyst has remained elusive, as over-oxidation is a facile and thermodynamically favored process. Recent studies by the lead investigator's group has demonstrated that boron-containing catalysts (hBN, BNNT, WB, among others) are highly selective catalysts for the ODH of light alkanes. For propane ODH, propylene selectivity as high as 80% can be obtained up to 20% conversion, compared to 60% propylene selectivity at 10% propane conversion for the state-of-the-art vanadium oxide-based catalyst. Given the recent discovery of this class of materials as ODH catalysts, there are many fundamental questions that need to be answered regarding the active sites and their formation. Controlled synthesis, state-of-the-art solid-state NMR (SSNMR) spectroscopy, and computational modelling will be utilized to gain insights into the catalytically active site(s) and build up a structure-performance relationship for boron-containing ODH catalysts. The work will contribute to a molecular-level understanding of a complex problem that is of industrial importance. Our multidisciplinary approach comprised of synthesis, SSNMR characterization, catalytic testing, and computational modelling will train the participating students to use information from a variety of fields to develop a detailed picture of a complex system. Additionally, the collaborative nature of this work will help the students grow as productive members of a research team. Beyond the targeted reactions, the study will be of value to the broader catalysis community because of the generalized catalytic insights and the methods developed for characterization of heterogeneous materials.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.