Mechanistic study of N8- polynitrogen synthesis and its oxygen reduction reaction

燃料电池是通过电化学反应将燃料的化学能直接转化为电能的装置。然而，铂催化剂的高昂成本阻碍了燃料电池的广泛应用。尽管经过几十年的研究，但很少有非贵金属燃料电池催化剂能与铂的性能和稳定性相媲美。该项目将研究作为燃料电池催化剂的低成本铂替代品，从而帮助实现燃料电池技术在能源领域的更高渗透率，并增强我国的能源安全。该项目还将包括教育和推广计划，以提高所有教育水平的能源意识，并建立一支在能源技术方面训练有素的未来劳动力队伍。来自新泽西州纽瓦克新泽西理工学院的王先勤博士领导的项目涉及探索多壁碳纳米管负载的聚合氮(PN)作为质子交换膜(PEM)燃料电池潜在使用的阴极催化剂。该项目旨在促进对PN合成和碳支撑的聚合物氮物种在促进氧还原反应(ORR)方面的作用的基本了解。与阴离子多氮物种相关的活性中心将与增强的O=O键还原有关，并通过先进的表征工具和密度泛函理论(DFT)对电化学还原机理有更详细的了解。特别是，O2的化学吸附模式将通过原位壳层隔离纳米颗粒增强拉曼光谱(Shiners)来探索，结合动力学实验和理论计算，可以更深入地了解ORR机理及其与催化剂结构的关系。这些结果将为无金属、绿色催化材料作为氢、甲醇、葡萄糖或生物质燃料电池的氧还原催化剂提供基础。这一努力的成功结果将导致非金属聚合氮在其他应用中的使用，如温和和选择性的氧化反应、加氢反应以及生物质转化和可持续化学的多用途应用。王博士积极参与激励年轻学生，特别是女性和代表不足的少数族裔，通过研究培养他们对科学的兴趣。她将为不同的研究生、本科生和K-12学生提供机会，在这个跨学科的研究项目中进行合作，并与来自不同领域的科学家合作。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Fuel cells are devices for direct conversion of the chemical energy of a fuel into electricity through electrochemical reactions. However, widespread implementation of fuel cells has been hampered by the high cost of the platinum catalyst. Despite many decades of research, few non-precious metal fuel cell catalysts have been found that can rival the performance and stability of platinum. The project will investigate low-cost alternatives to platinum as fuel cell catalysts, thus helping to achieve higher penetration of fuel cell technology into the energy sector and increasing our Nation's energy security. The project will also include educational and outreach programs that will enhance energy awareness at all educational levels and build a future workforce highly trained in energy technology.The project under Dr. Xianqin Wang from New Jersey Institute of Technology, Newark, NJ, involves exploring polymeric nitrogen (PN) supported on multi-walled carbon nanotubes as the cathode catalyst for potential use in proton exchange membrane (PEM) fuel cells. The project seeks to advance fundamental understanding of PN synthesis and the role of the carbon-supported polymeric nitrogen species to promote the oxygen reduction reaction (ORR). The active sites associated with the anionic polynitrogen species will be linked to enhanced O=O bond reduction and more detailed understanding of the electrochemical reduction mechanism as obtained from both advanced characterization tools and density functional theory (DFT). In particular, the O2 chemisorption mode will be probed under reaction conditions by in situ shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS), which when combined with kinetic experiments and theoretical calculations, can shed deeper insight regarding the ORR mechanism and its relationship to catalyst structure. The results will provide the basis for metal-free, green catalytic materials as oxygen reduction catalysts for hydrogen, methanol, and glucose or biomass powered fuel cells. Successful results from this effort will lead to use of non-metallic polymeric nitrogen in other applications, such as mild and selective oxidation reactions, hydrogenation reactions and multipurpose applications in biomass conversion and sustainable chemistry. Dr. Wang is actively involved in inspiring young students, especially female and underrepresented minorities, to develop their interests in science through research. She will provide opportunities for a diverse group of graduate, undergraduate, and K-12 students to collaborate in this interdisciplinary research project and work with scientists from different fields.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.