CAREER: Single-Atom Alloy Nanocrystals for Catalyzing Sustainable Nitrogen Cycling

职业：用于催化可持续氮循环的单原子合金纳米晶体

• 批准号: 2317302
• 负责人: Huiyuan Zhu
• 金额: $ 59.29万
• 依托单位: University of Virginia Main Campus
• 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: 2023-01-15 至 2027-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2317302&HistoricalAwards=false
• 关键词: CAREER; Single; Atom; Alloy; Nanocrystals

The industrial production of fertilizer – produced from ammonia (NH3) generated by the energy-intensive, fossil fuel-dependent Haber-Bosch (H-B) process - has disrupted the natural nitrogen cycle, resulting in groundwater pollution from nitrates (NO3-). The project utilizes electrochemistry to react nitrate compounds with hydrogen (derived sustainably from water) to manufacture NH3, while simultaneously decomposing the nitrate pollutants and restoring balance to the nitrogen cycle. Specifically, the research focuses on the discovery and design of catalysts that enable efficient nitrate-to-ammonia transformation driven by renewable electricity. Beyond the technical aspects, the project will train students from diverse groups at the interface of catalysis, chemistry, and engineering. The research will be integrated with educational and outreach efforts to illustrate the importance of sustainability in daily life while stimulating excitement for STEM amongst K-12 youth, especially those from low-income families. The electrochemical nitrate reduction reaction (NO3RR) offers a potentially attractive distributed NH3 production route, because it utilizes nitrate pollutants as the N-source, thus circumventing activation of the strong N≡N triple bond associated with the H-B process. The project will develop design strategies for single-atom alloy (SAA) electrocatalysts for the NO3RR and advance the fundamental understanding of both the catalytic active sites and the elementary mechanisms. The project is built on the central hypothesis that surface doping of Cu nanocrystals with isolated metal atoms (for example, Pt, Pd, Rh, or Ru) creates well-defined sites that activate water molecules and generate H-atoms that spill over to the Cu. The H-atoms hydrogenate N-species at low overpotentials and selectively tailoring of the binding strength of NO3RR surface intermediates through narrowly distributed d-states of single atoms for high-rate production of NH3, can potentially go beyond adsorption-energy scaling limitations. Catalyst synthesis, characterization, and electrochemical evaluation will be facilitated by advanced characterization techniques including operando surface-enhanced infrared absorption spectroscopy, differential electrochemical mass spectrometry, in-situ X-ray absorption spectroscopy, advanced electron microscopy, and computational tools such as density functional theory. The educational components of the project include (1) integrating research into the curriculum, (2) interdisciplinary student training, (3) involving diverse underrepresented students in science and engineering, and (4) implementing STEM-based outreach programs through the Center for Enhancement of Engineering Diversity at Virginia Tech and summer programs at Wonder Universe: A Children’s Museum. In addition, the newly launched Virginia Clean Energy and Catalysis Club will be leveraged as a platform to promote student training. The outreach plan also includes the development of an interactive play-based pedagogical platform, “Sustainable City in Minecraft,” that will provide young students the opportunity to design and construct a futuristic sustainable city.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.

肥料的工业生产是由氨（NH3）产生的，该氨（NH3）由能源密集型化石燃料依赖性Haber-Bosch（H-B）工艺产生，破坏了自然氮循环，从而造成了硝酸盐的地下水污染（NO3-）。该项目利用电化学对硝酸盐化合物与氢（从水的可持续发展）进行反应，同时分解了硝酸盐污染物并将平衡恢复到氮气周期。具体而言，该研究的重点是对催化剂的发现和设计，这些催化剂能够通过可再生电力驱动的有效的硝酸盐对肌电转化。除了技术方面，该项目还将在催化，化学和工程界面上培训来自潜水员群体的学生。这项研究将与教育和外展工作相结合，以说明可持续性在日常生活中的重要性，同时刺激K-12年轻人（尤其是来自低收入家庭的年轻人）对STEM的兴奋。电化学硝酸盐还原反应（NO3RR）提供了潜在的有吸引力的分布式NH3生产途径，因为它利用硝酸盐污染物作为N-源，因此避免了与H-B过程相关的强N区三键的激活。该项目将为NO3RR制定单原子合金（SAA）电催化剂的设计策略，并提高对催化活性位点和基本机制的基本理解。该项目建立在中心假设的基础上，即用孤立的金属原子（例如，Pt，Pd，Rh或Ru）表面掺杂Cu纳米晶体会产生定义明确的位点，从而激活水分子并产生H原子，从而溢出到CU上。低电势下的H原子氢化N种体和通过狭窄的单个原子的狭窄分布的D园的结合强度选择性地定制了NH3的高速生产，可能会超出附加能力缩放量表的限制。催化剂的合成，表征和电化学评估将通过先进的表征技术来制备，包括操作表面增强的基础抽象光谱，差异电化学质谱法，原子X射线抽象镜头，高级电子镜，高级电子镜检查和计算工具，例如密度功能理论。该项目的教育组成部分包括（1）将研究整合到课程中，（2）跨学科的学生培训，（3）涉及科学和工程领域的代表性不足的学生，以及（4）通过在Wonder宇宙的弗吉尼亚技术和夏季计划增强工程多样性的基于STEM的外展计划：一个儿童博物馆。此外，新推出的弗吉尼亚州清洁能源和催化俱乐部将被利用，作为促进学生培训的平台。外展计划还包括开发一个基于互动游戏的教学平台“ Minecraft中的可持续城市”，该平台将为年轻学生提供设计和建造未来派可持续性城市的机会。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的影响来审查审查标准来通过评估来通过评估来提供的支持。

项目成果

Synthesis of core/shell nanocrystals with ordered intermetallic single-atom alloy layers for nitrate electroreduction to ammonia

• DOI: 10.1038/s44160-023-00258-x
• 发表时间: 2023-07-01
• 期刊: NATURE SYNTHESIS
• 作者: Gao, Qiang;Yao, Bingqing;Zhu, Huiyuan
• 通讯作者: Zhu, Huiyuan