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

CBET-1604008 PI：Virkar，Anil V.拟议的工作涉及高温固体氧化物电解槽(SOEC)的氧(即空气)电极的稳定，SOEC主要用于将水转化为氢。这种装置可能是以风能或太阳能为基础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。这项拟议的工作解决了固体氧化物电化学电池中的一个基本稳定性问题，该问题被许多设备共享，包括固体氧化物燃料电池、运行在可逆模式下的电池和某些电池。因此，这项研究的结果可能会比SOEC本身更广泛地有利于能量存储和转换设备。SOEC通常在高电极过电位下运行，这反过来会导致电极-电解液界面上有效氧压的建立，在某些情况下会形成气泡。氧的积聚会导致内部裂纹和电极剥离。该项目基于这样的命题，即由离子导电粒子电极和电解液材料组成的纳米结构电极可以显著降低极化电阻，降低氧压(和气泡形成的风险)，从而抑制降解。为此，我们将通过各种技术在电解液盘和燃料电极支持的电池上沉积10-50 nm范围内的纳米钙钛矿氧电极，然后用电化学阻抗谱对其极化电阻进行表征。测量的极化电阻将与微观结构分析和计算相结合来预测退化行为，并将其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.