CAREER: Probing Oxygen-Mediated Electrochemical Processes of Oxides at High Spatial and Temporal Resolution

非技术描述：固体氧化物燃料电池-直接通过氧化燃料产生电力的设备-被认为是清洁和高效能源转换的途径。由于这些装置的性能在很大程度上取决于在空气电极处发生的基于氧的电化学反应的动力学，因此已经进行了大量的努力来改善电极性能并在基础水平上更好地理解它。虽然反应的每个基本过程本质上是由局部材料性质和几何形状决定的纳米级现象，但电化学性质主要通过批量（体积平均）测量进行分析。为了在电极设计方面取得突破，需要对纳米级的过程有更深入的了解。该项目旨在通过原位纳米级观察对电化学反应进行新的见解，这是由一种新型的扫描探针显微镜类型的仪器实现的。该项目正在培训本科生和研究生研究人员（包括代表人数不足的少数民族学生），以便他们今后在能源技术部门就业。技术详细信息：固体氧化物燃料电池和电解槽的性能在很大程度上受到氧还原/析氧反应（ORR/OER）动力学的影响。虽然人们已经做出了巨大的努力来理解反应的基础机制，但反应过程中的纳米级过程在很大程度上是未知的。该项目旨在通过利用一种新型的基于扫描探针的微尺度加热器装置，通过原位纳米级观察来促进对ORR/OER过程的理解。该研究有三个重要方面：1）展示了一种新的基于高温扫描探针的方法，用于在操作氧活性下的电化学表面反应和电荷传输动力学的原位纳米级表征; 2）开创了一种新的热活化过程的时间分辨纳米级表征; 3）提供了关于ORR/OER和纳米级相关电荷传输的更深入的见解。该项目为研究生和本科生提供了广泛的研究机会，通过将研究纳入研讨会和课程来加强课程，并促进有效的教育K-12学生从当地和周围的农村社区在中央谷通过对该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的评估支持知识价值和更广泛的影响审查标准。

NON-TECHNICAL DESCRIPTION: Solid oxide fuel cells - devices that produces electricity directly from oxidizing a fuel - are considered routes for clean and efficient energy conversion. Since the performance of these devices is largely determined by the kinetics of the oxygen-based electrochemical reaction occurring at the air electrode, intense efforts have been made to improve the electrode performance and better understand it on a fundamental level. While each elementary process of the reaction is intrinsically a nanoscale phenomenon dictated by local material properties and geometry, the electrochemical properties have been mostly analyzed through bulk (volume-averaged) measurements. To obtain a breakthrough in electrode design, a more thorough understanding of the process at the nanoscale is needed. This project aims for new insights about the electrochemical reactions through in situ nanoscale observations, which is enabled by a novel scanning probe microscopy type instrument. This project is training undergraduate and graduate researchers (including underrepresented minority students) for their future employment in the energy technology sector. TECHNICAL DETAILS: The performance of solid oxide fuel cells and electrolyzers are largely affected by the kinetics of oxygen reduction/evolution reactions (ORR/OER). While intense efforts have been made to understand the underpinning mechanisms of the reactions, nanoscale processes during the reaction are largely unknown. This project aims to advance the understanding of ORR/OER processes through in situ nanoscale observations by leveraging a novel scanning probe-based setup with a microscale heater. There are three significant aspects of this research: 1) demonstrating a new high temperature scanning probe-based approach for in situ nanoscale characterizations of electrochemical surface reaction and charge transport kinetics under operating oxygen activities; 2) pioneering a novel time-resolved nanoscale characterization of thermally-activated processes; 3) providing deeper insight regarding the ORR/OER and related charge transport at the nanoscale. The project provides extensive research opportunities for graduate and undergraduate students, enhances curricula by incorporating research into seminars and courses, and promotes effective education for K-12 students from the local and surrounding rural communities in the Central Valley through the on-campus Engineering Service Learning.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.