Highly Active Nanostructured Electrodes for High Temperature, Degradation-Resistant Solid Oxide Reversible Cells

本文提出的工作涉及用于高温固体氧化物电解电池（SOECs）的氧（即空气）电极的稳定性，SOECs主要用于将水转化为氢。这种装置可能是基于风能或太阳能的可持续能源和化学品未来的关键组成部分。该项目将专注于纳米颗粒材料的合成，这些材料有可能提高soec的效率和稳定性。提出的工作解决了固体氧化物电化学电池的一个基本稳定性问题，这个问题在许多设备中都存在，包括在可逆模式下工作的固体氧化物燃料电池和某些电池。因此，这项研究的发现可能会比单独的soec更广泛地有益于能量存储和转换设备。soec通常在高电极过电位下工作，这反过来会导致电极-电解质界面上有效氧压的积累，在某些情况下会达到气泡形成的程度。氧气积聚会导致内部开裂和电极分层。该项目基于由离子导电颗粒电极和电解质材料组成的纳米结构电极可以大幅降低极化电阻，降低氧压（以及气泡形成的风险），从而抑制降解的命题。为此，将采用多种技术在电解质片和燃料电极支撑电池上沉积10-50 nm的纳米结构钙钛矿氧电极，然后利用电化学阻抗谱对其极化电阻进行表征。测量的极化电阻将结合微观结构分析和计算来预测降解行为，并将与实验研究进行比较。

CBET - 1604008 PI: Virkar, Anil V. The proposed work deals with the stabilization of oxygen (i.e. air) electrodes for high-temperature solid oxide electrolysis cells (SOECs), which are used primarily for converting water to hydrogen. Such devices could be a key component of a sustainable energy and chemicals future based on wind or solar energy. The project will focus on synthesis of nanoparticle materials that have potential to improve the efficiency and stability of SOECs. The proposed work addresses a fundamental stability problem in solid oxide electrochemical cells that is shared among a number of devices including solid oxide fuels cells operating in the reversible mode and certain batteries. Thus, findings that will come out of the study can potentially benefit energy storage and conversion devices more broadly than SOECs alone.SOECs typically operate at high electrode overpotentials, which in turn, can result in build up of effective oxygen pressure at the electrode-electrolyte interface, in some cases to the point of bubble formation. The oxygen build-up can lead to internal cracking and electrode delamination. Thi project is based on the proposition that nanostructured electrodes consisting of ionically-conducting particles electrode and electrolyte materials can substantially lower polarization resistance, lower oxygen pressure (and the risk of bubble formation), and thereby suppress degradation. To this end, nanostructured perovskite oxygen electrodes in the range of 10-50 nm will be deposited on electrolyte discs and fuel electrode supported cells by a variety of techniques, and then characterized for polarization resistance using electrochemical impedance spectroscopy. The measured polarization resistance will be used in combination with microstructural analysis and calculations to predict degradation behavior that will be compared with experimental studies.