Current-Collector-Optional Measurements to Quantify Precious Metal and Polarization Impacts on Oxygen Surface Exchange Coefficients

电流收集器可选测量，用于量化贵金属和极化对氧表面交换系数的影响

• 批准号: 2241062
• 负责人: Jason Nicholas
• 金额: $ 49.71万
• 依托单位: Michigan State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-15 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2241062&HistoricalAwards=false
• 关键词: Current; Collector; Optional; Measurements; Quantify

Catalytic electrochemical devices are of increasing importance in alternative energy, environmental protection, and life-support technologies. The project focuses on a class of high-temperature devices including fuel cells, electrolyzers, oxygen generators, solar energy concentrators, and catalytic converters, that are often limited in performance by the slow exchange of oxygen with the surrounding atmosphere. Oxygen exchange is promoted by Mixed Ionic Electronic Conducting (MIEC) oxygen exchange catalysts. However, the identification of materials with improved oxygen exchange is presently limited by experimental artifacts associated with measuring the catalyst’s oxygen exchange rate (as typically characterized by a rate coefficient known as k(chem)). The project will quantify the sources of errors and lack of lab-to-lab reproducibility in traditional electrochemical k(chem) measurements, while demonstrating the effectiveness of a novel non-electrochemical thin-film method for accurately measuring oxygen exchange rates. Beyond the technical aspects, the project involves educational and outreach activities ranging from introducing 4-8th grade girls to engineering to teaching a course at the Michigan State Grandparent University Summer Camp. Recent experiments by the investigator’s group, and others, have demonstrated that precious metal current collectors, even unpolarized ones, can alter high-temperature MIEC k(chem) values. However, the full extent to which precious metal surface additions and/or electric polarization influence high-temperature MIEC k(chem) values, and the mechanisms by which this occurs, have yet to be fully explored. Hence, the objective of the project is to: 1) quantify the impact intentionally-added Pt surface additions and/or electric polarization have on the 400-600°C k(chem) of Pulsed Laser Deposited (PLD) praseodymium cerium oxide (PCO) thin films, 2) determine the mechanisms by which these fabrication and testing modifications alter the PCO k(chem), and 3) identify possible sources of previously-unrecognized, inadvertent precious metal contamination. This will be achieved by comparing the k(chem) values obtained from an in situ, non-contact, current-collector-optional wafer curvature measurement technique developed in the investigator’s group with those obtained via simultaneous Electrical Conductivity Relaxation and Electrochemical Impedance Spectroscopy. In addition, surface and bulk thin film composition and structural characterization techniques (such as X-Ray Diffractometry, Scanning Electron Microscopy, X-Ray Photoelectron Spectroscopy, and Secondary Ion Mass Spectrometry) will be used to identify relationships between k(chem) and materials properties.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.

催化电化学设备在替代能源，环境保护和生命支持技术中的重要性越来越重要。该项目着重于一类高温设备，包括燃料电池，电解器，氧气发电机，太阳能浓缩物和催化转化器，这些转化器通常通过与周围气氛的氧气缓慢交换而在性能中受到限制。氧交换是通过混合离子电子传导（MIEC）氧交换催化剂来促进的。然而，通过与测量催化剂的氧汇率相关的实验伪像限制了对氧交换的材料的识别（通常为相关的k（chem））。该项目将量化传统电化学K（Chem）测量的错误来源和缺乏实验室到LAB的可重复性，同时证明了一种新型的非电气化学薄膜方法的有效性，以准确测量氧气汇率。除技术方面外，该项目还涉及从介绍4至8年级的女孩到工程学的教育和外展活动，在密歇根州祖父母大学夏令营上教课程。研究者组和其他人的最新实验表明，贵金属电流收集器，甚至是未偏光的收集器，都可以改变高温MIEC K（CHEM）值。但是，贵金属表面添加和/或电化极化影响高温MIEC K（化学）值的全部程度以及发生这种情况的机制尚未得到充分探索。因此，该项目的目的是：1）量化有意添加的PT表面添加和/或电化极化对400-600°C K（CHEM）的脉冲激光（CHEM）的脉冲激光（PLD）（PLD）氧化物（PCO）比例（PCO）薄膜（PCO）薄膜，2）确定这些制造和测试的机制（2），并确定这些制造的机制（CO）的机制（CO），并可能识别POCO（pCO）（CO）的机制（CO）。以前未经公认的无意的贵金属污染。这将通过比较从研究者组中开发的原位，非接触，电流 - 捕获晶圆的曲率测量技术与通过简单的电导率松弛和电化学征收频谱获得的k（化学）值与通过简单的电导率松弛和通过简单的电导率松弛和通过简单的电导率获得的值进行比较。此外，表面和大量的薄膜组成和结构表征技术（例如X射线衍射法，扫描电子显微镜，X射线光电光谱和次级离子质谱法）将用于确定K（Chem）的关系和材料之间的关系，以评估NSF的构建范围，以识别NSF的构建范围。 标准。