GOALI: Probing Temporospatial Correlations at the Nanoscale in High-Temperature Electrocatalysts

摘要标题：GALI：用于成像纳米尺度电催化剂局部活性的新扫描探针方法我国未来能源基础设施的一个关键要求是能够有效地将化学(燃料)和电力形式的能源相互转换。这种相互转化是通过在高温下使用氧化物电催化剂来促进的，氧化物电催化剂提供了分子和电子可以在其上相互作用的高活性表面。不幸的是，控制电催化剂活性和降解的因素还不是很清楚。该项目旨在开发新的扫描探头方法，可以在高达500-600°C的操作期间以纳米分辨率对表面发生反应的地点和时间进行实时成像。该奖项汇集了华盛顿大学在电催化和扫描探头方法方面的专业知识的Stuart Adler教授和蒋宇Li教授，以及领先的扫描探头仪器开发商--SAHORY Research的研究人员负责人Roger Proksch博士，以开发一种先进的高温扫描探头系统。该仪器和由此产生的研究工作将在我们如何研究电催化剂方面取得重大进展，并提供关键的见解，导致电催化领域的新技术进步。该项目还将为两名博士生提供高级研究生教育，为本科生提供研究机会，并支持西雅图地区K-12学生接受更深层次的科学教育。开发高温电催化剂面临的一个普遍挑战是缺乏对局部长度尺度(10-50 nm)的物理和化学速率的基本了解。越来越多的研究表明，这些材料在固-固或气-固界面附近的组成、结构和性能都与块体有很大的偏差。本发明的目的是开发扫描探针技术(基于对局部晶格应变、电导率和表面功函数的测量)来量化和成像原位条件下多孔高温电催化剂中的局部速率。该项目旨在1)将应变、功函数和其他局部可测量的特性与带电缺陷浓度的变化联系起来，2)在工作电极上现场实施扫描探头技术作为局部动态的见证，以及3)扩展当前的实验能力以获得更高的温度(500-600°C)。最终，多孔电极的活性区域将被成像为变量的函数，从而提取关于发生在电极/电解液界面附近的局部水平上的分子反应、表面传输和整体传输的相对速率的基本信息。

Abstract Title: GOALI: New Scanning Probe Methods for Imaging Local Activity in Electrocatalysts on Nanometer Length ScalesA key requirement for our nation's future energy infrastructure is an ability to efficiently interconvert chemical (fuel) and electrical forms of energy. Such interconversion is facilitated by using oxide electrocatalysts at high temperature, which provide highly active surfaces upon which molecules and electrons can interact. Unfortunately the factors governing activity and degradation of electrocatalysts are not very well understood. This project seeks to develop new scanning probe methods that can image in real time, and during operation at up to 500-600°C, where and when reactions occur on the surface, with nanometer resolution. This GOALI award brings together Professors Stuart Adler and Jiangyu Li with expertise in electrocatalysis and scanning probe methods at the University of Washington and Dr. Roger Proksch, head of the research staff at Asylum Research, a leading developer of scanning probe instruments to develop an advanced high-temperature scanning probe system. This instrument and the resulting research work will lead to major advances in how we study electrocatalysts, as well as provide key insights leading to new technological advances in electrocatalysis. The project will also provide advanced graduate education to two PhD students, provide research opportunities for undergraduates, and support the mentorship of Seattle-area K-12 students in pursuing a deeper scientific education. A universal challenge facing development of high temperature electrocatalysts is a lack of fundamental understanding of physical and chemical rates at local length scales (10-50 nm). A growing body of research shows that the composition, structure, and properties of these materials near solid-solid or gas-solid interfaces deviate substantially from the bulk. The purpose of this GOALI is to develop scanning probe techniques (based on measurement of local lattice strain, conductivity, and surface work function) to quantify and image local rates in porous high-temperature electrocatalysts under in-situ conditions. This project seeks to 1) link strain, work function, and other locally measurable properties to variations in charged defect concentrations, 2) implement scanning probe techniques in-situ on working electrodes as witnesses of local dynamics, and 3) extend the current experimental capabilities to access higher temperatures (500-600°C). Ultimately, the active region of a porous electrode will be imaged as a function of variables, resulting in the extraction of basic information about relative rates of molecular reactions, surface transport, and bulk transport occurring at a local level near the electrode/electrolyte interface.