Collaborative Research: INFEWS N/P/H2O: Electrochemical Approaches to Sustainable Dinitrogen Fixation

在这个由化学部化学催化计划资助的项目中，来自北卡罗来纳大学教堂山分校(UNC)、耶鲁大学和罗格斯大学的科学家正在合作开发可持续的电化学固定氮(N2)的方法。可持续的固氮是食品、能源和水化学中的一系列挑战的核心。目前的全球粮食生产是通过使用合成肥料来实现的，合成肥料是由固氮过程产生的，该过程从氮气和氢气(H2)中产生氨(NH3)，但对能源和环境造成了巨大的负面影响，消耗了世界约2%的能源--S化石燃料衍生能源供应。在这个项目中，亚历山大·米勒教授(北卡罗来纳大学)，教授。詹姆斯·梅尔和帕特里克·霍兰德(耶鲁)，以及教授。艾伦·戈德曼和盖尔·霍赫曼(罗格斯大学)正在探索新的、可持续的固氮方法。将开发新的化学，使电化学固氮过程的开发成为可能，这些过程不需要消耗化石燃料来生产氨和硝酸盐。可持续性和政策分析将评估对全球农业和能源部门产生变革性影响的可能性(包括考虑将氨作为一种可能的液体运输燃料)。该项目将对研究生和博士后研究人员进行跨学科、以问题为基础的科学方法培训，并对机构基础设施产生积极影响。这项研究的主题和结果将作为一个平台，向非科学家传授化学催化在工业、农业和现代社会中的重要性。跨学科研究团队在催化剂设计和合成、电催化、机理研究、可持续性和政策分析方面具有优势。氮气固定的化学方法包括过渡金属-电催化的氮气还原裂解为硝基中间体。这些氮化物中间体可以经历(A)通过质子耦合电子转移(PCET)将氮化物还原为NH3，或(B)氮化物氧化为硝酸。强健且可调的钳形配体的中晚期过渡金属络合物将是实验的焦点，辅以计算研究以将反应性与分子性质相关联并指导催化剂的开发。将分析潜在的电化学固氮过程的成本，以估计对一系列因素的依赖，如电源的多样性、可持续能源的间歇性和政府政策。

In this project funded by the Chemical Catalysis Program of the Chemistry Division, scientists from the University of North Carolina at Chapel Hill (UNC), Yale University, and Rutgers University are collaborating to develop approaches to sustainable electrochemical fixation of nitrogen (N2). Sustainable nitrogen fixation is central to the nexus of challenges in food, energy, and water chemistry. Current global food production is enabled by the use of synthetic fertilizer that is produced by nitrogen fixation processes that generate ammonia (NH3) from nitrogen and hydrogen (H2), but leave a dramatic negative impact on energy and the environment, consuming about 2% of the world?s fossil fuel-derived energy supply. In this project, Prof. Alexander Miller (UNC), Profs. James Mayer and Patrick Holland (Yale), and Profs. Alan Goldman and Gal Hochman (Rutgers) are exploring new, sustainable methods for nitrogen fixation. New chemistry will be developed that could enable the development of electrochemical nitrogen fixation processes that do not require consumption of fossil fuels to produce ammonia and nitrates. Sustainability and policy analysis will assess the potential for transformative impact on global agriculture and energy sectors (including consideration of ammonia as a possible liquid transportation fuel). The project will train graduate students and postdoctoral researchers in interdisciplinary problem-based scientific methods and positively impact institutional infrastructure. The topic and the results of the research will be used as a platform to teach non-scientists about the importance of chemical catalysis in industry, agriculture, and modern society in general. The interdisciplinary research team has strengths in catalyst design and synthesis, electrocatalysis, mechanistic studies, and sustainability and policy analysis. The chemical approach to N2 fixation involves transition-metal-electrocatalyzed reductive splitting of N2 into nitrido intermediates. These nitrido intermediates can undergo (a) nitride reduction to NH3 by proton-coupled electron transfer (PCET), or (b) nitride oxidation toward nitric acid. Middle-to-late transition metal complexes of robust and tunable pincer ligands will be an experimental focus, with complementary computational studies to correlate reactivity with molecular properties and guide catalyst development. The cost of potential electrochemical N2 fixation processes will be analyzed, to estimate the dependence on a range of factors such as diversity of electricity sources, intermittency of sustainable energy, and governmental policy.