CAREER: Engineering electrode-electrolyte interfaces through electrolyte selection for improved performance in lithium-air batteries and fuel cell electrocatalysis

摘要- Viswanathan， 1554273为了环保电动汽车的大众市场采用，需要在比能量和成本方面在电池技术上取得突破。比能，也称为能量密度，是一种物质的储存热量或其他热力学性质，对于这些目的，它应该是它的有用的或可提取的能量。在考虑的候选化学物质中，非水锂-空气电池因其高比能和相对较低的成本而具有吸引力。然而，有限的放电容量和可充电性是限制其实用性的两个关键问题。在不牺牲电池可充电性的前提下，利用电解质添加剂提高现有非水锂-空气电池的有限放电容量。这些方法和发现也将广泛适用于目前正在研究的其他金属-空气电池技术，如钠-空气、镁-空气和钾-空气。坚固的电极/电解质界面是燃料电池和电池长期可靠性的关键要求。本提案通过两个模型问题来解决电化学系统背景下的中尺度电极/电解质问题：(i)通过电解质修饰来调整电极/电解质界面，以定制Pt族金属在水氧还原反应中的活性和选择性；（ii）设计兼容的电极和电解质组合，在锂空气电池中具有界面稳定性，同时可溶解放电产物。如果成功，这些电池可以促进电动汽车的采用，以减少排放，提高效率，并增加国内能源安全。PI成功地运营了卡内基梅隆大学统计热力学的大规模开放在线课程（MOOC），并打算每年继续提供这种课程。他将通过开发可以远程3D打印的学习工具包来补充MOOC。他还将开发一门关于电化学能源系统的新课程，并将课程笔记开发成交互式和动画丰富的电子教科书，并将在代表性不足的匹兹堡公立学校举办“电池是如何工作的？”研讨会，目的是说明热力学的基本原理。

Abstract - Viswanathan, 1554273For the mass-market adoption of environmentally benign electric vehicles a breakthrough in battery technology in terms of specific energy and cost is needed. Specific energy, also known as energy density, is the stored heat or other thermodynamic property of a substance, which for these purposes should be its useful or extractable energy. Among the candidate chemistries being considered, non-aqueous Li-air batteries are attractive due to their high specific energy and relatively low cost. However, the limited discharge capacity and rechargeability are two key issues that limit their practicality. The proposed research of using electrolyte additives could increase the limited discharge capacity of current non-aqueous Li-air batteries without sacrificing battery rechargeability. The methods and findings will also be broadly applicable to other metal-air battery technologies currently being pursued, such as sodium-air, magnesium-air and potassium-air. Robust electrode/electrolyte interfaces are a crucial requirement for the long-term reliability of fuel cells and batteries. This proposal addresses the mesoscale electrode/electrolyte problem in the context of electrochemical systems using two model problems: (i) tune the electrode/electrolyte interface through electrolyte modification to tailor the activity and selectivity of Pt group metals for aqueous oxygen reduction reaction and (ii) design compatible electrode and electrolyte combinations that possess interfacial stability in lithium-air batteries while solubilizing the discharge product.If successful, these batteries could advance the adoption of electric vehicles for reduced emissions, greater efficiency, and increased domestic energy security. The PI ran a successful massive open online course (MOOC) from Carnegie Mellon University on Statistical Thermodynamics and intends to continue offering this annually. He will supplement the MOOC by developing learning kits, which can be remotely 3D printed. He will also develop a new course on electrochemical energy systems and develop the course notes into an interactive and animation-rich in-progress electronic-textbook and will conduct workshops on "How batteries work?" at underrepresented Pittsburgh public schools with the aim of illustrating basic principles of thermodynamics.