CAREER: Understanding the Interdependence of Cation and Anion Adsorption for Electrocatalytic Nitrate Reduction

职业：了解电催化硝酸盐还原中阳离子和阴离子吸附的相互依赖性

• 批准号: 2236770
• 负责人: Nirala Singh
• 金额: $ 66.93万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2028-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2236770&HistoricalAwards=false
• 关键词: CAREER; Understanding; Interdependence; Cation; Anion

Providing fuels and chemicals without negative environmental impacts requires new catalysts and processes that can be driven by renewable electricity instead of fossil fuels. Electrocatalysis is a method to use renewable electricity to drive low temperature and pressure reactions for distributed sustainable fuel generation, waste treatment, and energy storage. Understanding electrocatalytic reaction rates will increase the energy efficiency and economic viability of new electrocatalytic processes. This CAREER project will study electrocatalysis to convert waste nitrate species to valuable products such as ammonia as a case study for sustainable chemical processes. Nitrate is a harmful pollutant that results from industrial effluents and agricultural runoff, while ammonia is a useful fuel and fertilizer. For electrocatalytic nitrate conversion to be viable, the negatively charged nitrate anion must interact with an electrified electrocatalyst surface in the presence of positively charged cations to reduce nitrate at the desired rates. This project will step-by-step add in the complexity of these factors to develop an understanding of what impacts electrocatalytic reaction rates. In addition to studying this model electrocatalytic reaction, the next generation of scientists and engineers will be trained for the new challenges for a switch to a more sustainable, environmentally friendly chemical economy through coursework and hands on training. The complex interaction of reactants, ions, and the electrocatalyst is incompletely understood for electrocatalysis. This project will study the interplay of the reacting molecule (i.e., nitrate), cations, the electrocatalyst surface, and potential in controlling electrocatalytic rates and selectivities of nitrate reduction. Structure-activity relations will be derived by measuring reaction rates on controlled metal and alloy surfaces and comparing to the measured adsorption energy of nitrate and other intermediates on those surfaces. By studying the interaction of the cations with the nitrate anion through UV-Vis, Raman, and X-ray absorption spectroscopy and comparing to kinetics, how these cation-anion interactions impact the adsorption energies and rates will be identified. The understanding of nitrate electrocatalytic reduction in electrolytes of interest to wastewater treatment will be improved by combining knowledge gained of these interactions. The new insights will be used to evaluate reaction rates for nitrate reduction in continuous electrocatalytic reactor systems. This project will develop methods to apply chemical reactor engineering principles to electrochemical reactors necessary for future advances in sustainable chemical and fuel generation. Specific broader impacts include updating undergraduate core curriculum for modern technologies, an electrochemistry applications and engineering course, Chem-E Car mentorship and outreach, and leveraging NSF I-CORPS to identify practical applications of electrocatalytic nitrate reduction.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.

提供没有负面环境影响的燃料和化学品需要新的催化剂和工艺，这些催化剂和工艺可以由可再生电力而不是化石燃料驱动。电催化是一种使用可再生电力驱动低温和低压反应的方法，用于分布式可持续燃料发电，废物处理和能量储存。了解电催化反应速率将提高新的电催化过程的能源效率和经济可行性。这个CAREER项目将研究电催化将废硝酸盐转化为有价值的产品，如氨，作为可持续化学过程的案例研究。硝酸盐是一种有害的污染物，来自工业废水和农业径流，而氨是一种有用的燃料和肥料。为了使电催化硝酸盐转化可行，带负电荷的硝酸根阴离子必须在带正电荷的阳离子存在下与带电的电催化剂表面相互作用，以期望的速率还原硝酸根。该项目将逐步增加这些因素的复杂性，以了解影响电催化反应速率的因素。除了研究这种电催化反应模型外，下一代科学家和工程师还将接受培训，以应对新的挑战，通过课程和实践培训转向更可持续，更环保的化学经济。反应物、离子和电催化剂之间复杂的相互作用对于电催化还没有完全理解。该项目将研究反应分子的相互作用（即，硝酸盐）、阳离子、电催化剂表面和控制硝酸盐还原的电催化速率和选择性的电势。通过测量受控金属和合金表面上的反应速率，并与硝酸盐和其他中间体在这些表面上的实测吸附能进行比较，得出结构-活性关系。通过UV-Vis、拉曼和X射线吸收光谱研究阳离子与硝酸根阴离子的相互作用，并与动力学进行比较，确定这些阳离子-阴离子相互作用如何影响吸附能和吸附速率。硝酸盐电催化还原感兴趣的电解质废水处理的理解将得到改善，结合这些相互作用的知识。新的见解将用于评估连续电催化反应器系统中硝酸盐还原的反应速率。该项目将开发将化学反应器工程原理应用于电化学反应器的方法，这对于未来可持续化学和燃料发电的进步是必要的。具体的更广泛的影响包括更新现代技术的本科核心课程，电化学应用和工程课程，Chem-E汽车导师和推广，并利用NSF I-CORPS来确定电催化硝酸盐还原的实际应用。该奖项反映了NSF的法定使命，并被认为值得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来支持。