Enhanced Electrodes for Proton Conducting Solid Oxide Fuel Cells and Electrolyzers

随着间歇性可再生能源系统（如风能和太阳能）的大规模部署，供需匹配是一个重大问题。例如，风吹时产生的峰值功率必须与需求峰值相匹配。这就需要开发大型和高效的临时电力存储手段。一个有吸引力的选择是高性能，可逆，高效的燃料电池/电解槽系统。该系统将在电解槽模式下运行，以便在发电充足时将电能存储为化学能（氢）。然后，操作可以逆转，以在需求高峰期间提供电能。质子导电氧化物在高效高温固体氧化物燃料电池和电解槽中具有潜在的应用前景。虽然这些材料的输运性质正在得到越来越详细的研究，但目前关于这类材料的催化和电催化活性的知识非常有限。在氧离子导电材料的催化和电催化反应中，火星-范-克雷文机制对表面氧位点的还原和氧化（氧化还原）是一个核心步骤。提出的研究的中心假设是，类似的基于质子的Mars-van Krevelen机制将是质子导电氧化物催化循环的关键步骤。增强活性的主要途径是将过渡金属掺杂到氧化物晶格中，并在氧化物表面以纳米颗粒的形式掺杂。假设的电催化机制将通过同位素瞬态研究和与质子结合热力学、输运性质和晶体结构相关的测量反应动力学来验证。将制造和测试质子导电固体氧化物燃料电池和电解槽，以证明电催化和电极功能之间的联系。基于质子的Mars-van Krevelen机制的演示将为解释和提高质子导电氧化物电极的性能提供基础基础。更广泛的影响用质子导电氧化物代替氧离子导体为多相催化剂的发展提供了新的方向。这项多学科研究的结果将通过期刊出版物和会议报告传播到催化、电化学和固态离子学界。本科生将通过明确确定的、重点突出的研究项目，在这项研究中发挥积极作用。能源和环境领域正在进行的科学进步的重要性和潜在影响将通过在弗吉尼亚大学举行的“能源日”向公众传达。教师和研究生和本科生从整个校园积极参与这一领域将提供技术演示和讨论点。将通过扩大现有的一个小型项目，开发一种吸引中学生的重点方法。PI和PI实验室的研究生将花时间在当地中学，通过一系列实践项目向学生介绍工程的概念。这些课程将侧重于能源和可持续发展概念，并通过课堂教育加强学习成果。

0967829McIntoshMatching supply with demand is a significant issue with the large-scale deployment of intermittent renewable energy systems such as wind and solar power. For example, the peak power generated when the wind blows must be matched to periods of peak demand. This necessitates the development of large and efficient means of temporary power storage. One attractive option is a high performance, reversible, and efficient fuel cell/electrolyzer system. This system would operate in electrolyzer mode to store electrical energy as chemical energy (hydrogen) during periods of plentiful power generation. Operation can then be reversed to supply electrical energy during periods of peak demand.Intellectual MeritProton conducting oxides have potential application in efficient high temperature solid oxide fuel cells and electrolyzers. While the transport properties of these materials are being studied in increasing detail, there is currently very limited knowledge regarding the catalytic and electrocatalytic activity of this class of material. Reduction and oxidation (redox) of surface oxygen sites by the Mars-van Krevelen mechanism is a central step in catalytic and electrocatalytic reaction on oxygen ion conducting materials. The central hypothesis of the proposed research is that an analogous proton-based Mars-van Krevelen mechanism will be a critical step in the catalytic cycle on proton conducting oxides. The central route to enhanced activity will be doping of transition metals both into the oxide lattice and as nanoparticles on the oxide surface. The hypothesized electrocatalytic mechanism will be validated by isotopic transient studies and the measured reaction kinetics related to proton incorporation thermodynamics, transport properties and crystal structure. Proton conducting solid oxide fuel cells and electrolyzers will be fabricated and tested to demonstrate the links between electrocatalysis and electrode function.The demonstration of a proton based Mars-van Krevelen mechanism will provide a fundamental basis from which the performance of proton conducting oxide electrodes may be interpreted and enhanced.Broader ImpactsReplacing oxygen ion conductors with proton conducting oxides can provide a new direction for heterogeneous catalyst development. The results of this multidisciplinary study will be disseminated to the catalysis, electrochemistry, and solid state ionics communities through journal publications and conference presentations. Undergraduate students will play an active role in this research through clearly identified, focused research projects. The importance and potential impact of ongoing scientific advances in the area of energy and the environment will be conveyed to the general public via "Energy days" to be held at the University of Virginia. Faculty and graduate and undergraduate students from across campus actively engaged in this field will provide technology demonstrations and discussion points. A focused approach to engaging middle school students will be developed by expanding a small existing program. The PI, as well as graduate students in the PI's laboratory, will spend a time at local middle schools introducing the concept of engineering to students through a series of hands-on projects. These will be focused on energy and sustainability concepts with learning outcomes reinforced through classroom education.