RUI: CAS: Nitrate/Nitrite Reduction Utilizing Hemilability and Redox-Activity

美国国家科学基金会化学系化学催化项目支持西华盛顿大学教授John Gilbertson和Timothy Kowalczyk的研究项目。他们的项目侧重于开发解决化肥污染的新方法。虽然肥料中的氮基化合物有助于作物生长，但它们会渗入自然水道、湖泊和海洋，使藻类大量繁殖，耗尽其他植物生存所需的氧气，从而造成“死区”。为了防止这种死区，该研究项目采用催化剂将这些含氮肥料从水中去除。这项研究将计算机计算与实验室实验结合起来，提出如何将这些化合物转化为污染更少的形式。特别令人感兴趣的是一种新的铁基催化剂家族，这种催化剂被设计成选择性地攻击最有问题的氮化合物，而不影响其他化合物。一组本科生正在制备和测试这种新型催化剂。这种实践培训为技术职业提供了必要的科学技能。本科研究人员的实验室训练辅以沟通和协作技能的训练。包括一系列广泛的外展活动，包括为来自不同背景的学生建立一个平台，让他们在多个机构层面参与科学讨论。这种培训促进了如何处理研究问题和解释数据的公开对话。这项工作通过与互补的科学和能源素养倡议相结合，为社区带来了好处。氧阴离子作为生命系统的基石起着至关重要的作用。例如，亚硝酸盐和硝酸盐是生物地球化学氮循环的核心。由于人类的入侵，例如过度使用化肥，历史上控制这一循环的平衡/不平衡正在发生变化。在化学系化学催化项目的支持下，西华盛顿大学的John Gilbertson教授和Timothy Kowalczyk教授正在开发一种催化剂，该催化剂将半水溶性和基于配体的氧化还原活性结合起来，用于研究亚硝酸盐和硝酸盐的还原。通过在二级配位球中开发具有半可溶路易斯碱和含硼路易斯酸的模块化吡啶二亚胺（PDI）配体家族，研究小组正在调整立体构型、pKa、酸度值和配体基还原电位，以生产氧化还原匹配的配合物，用于NOx还原。该项目通过提供跨学科的科学和专业培训来支持本科研究人员。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The Chemical Catalysis Program in the Division of Chemistry of the National Science Foundation supports the research project of Professors John Gilbertson and Timothy Kowalczyk at Western Washington University. Their project focuses on developing new ways of addressing pollution caused by fertilizers. While nitrogen-based compounds in fertilizers help crops grow, they can leach into natural waterways, lakes, and oceans fertilizing blooms of algae that deplete the oxygen which is required for other plants to live thus causing “dead zones”. To prevent such dead zones, this research project employes catalysts to remove these nitrogen-containing fertilizers from the water. The research combines computer calculations with laboratory experiments to suggest how these compounds can be converted to less polluting forms. Of particular interest is a new family of iron-based catalysts that are designed to selectively attack the most problematic nitrogen compounds, leaving others unaffected. The new catalysts are being prepared and tested by a team of undergraduate students. This hands-on training provides the scientific skills necessary for technical careers. The laboratory training of the undergraduate researchers is complemented by training in communication and collaboration skills. An extensive set of outreach activities are included, including the construction of a platform for students from diverse backgrounds to engage in scientific discussions across multiple institutional levels. This training facilitates an open dialogue of how research questions are approached and data interpreted. This work delivers benefits to the community through its integration with a complementary pair of science and energy literacy initiatives.Oxoanions play a vital role as the building blocks of living systems. For example, nitrite and nitrate are central to the biogeochemical Nitrogen Cycle. Through human intrusions such as the overuse of fertilizers, the equilibrium/disequilibrium that has historically governed this cycle is changing. With support from the Chemical Catalysis Program in the Division of Chemistry, Professors John Gilbertson and Timothy Kowalczyk at Western Washington University are developing catalysts that integrate hemilability and ligand-based redox activity to study nitrite and nitrate reduction. By developing a family of modular pyridinediimime (PDI) ligands with hemilabile Lewis bases and boron-containing Lewis acids in the secondary coordination sphere, the groups are tuning the sterics, pKa, Acidity Number, and ligand-based reduction potentials for the production of complexes that are redox-matched for NOx- reduction. The project supports undergraduate researchers by providing interdisciplinary scientific and professional training.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.