Development of carbon resistant Solid Oxide Electrolyzer Cells (SOEC) for CO2 utilization

高水平的大气二氧化碳正在导致气候变化，这造成了更极端的天气模式，以及其他问题。必须加快向无二氧化碳排放或低二氧化碳排放的能源系统的过渡，但这需要时间。随着我们迈向以可再生能源为基础的未来，我们必须应对当前以化石燃料为基础的能源模式所产生的二氧化碳。建议的解决办法包括碳捕获和封存(CCS)和碳捕获和利用(CCU)。 在CCS中，二氧化碳被捕获并注入到地质地层中。虽然CCS可以隔离大量二氧化碳，但它只能在有限的地点完成。在CCU，捕获的二氧化碳被用于生产化学品和燃料。虽然二氧化碳可以直接用作原料，但首先将二氧化碳转化为一氧化碳(CO)，然后利用一氧化碳(通常是氢气)形成新产品是有利的。二氧化碳可以通过电解转化为一氧化碳，在电解过程中，电能将二氧化碳分解为一氧化碳。 固体氧化物电解槽(SOEC)利用电能将二氧化碳和水转化为一氧化碳和氢气。像安大略省这样的省份，其发电的二氧化碳排放量较低，处于有利地位，可以利用这项技术。此外，SOEC可以很好地适应来自可再生能源的电力，可再生能源的特点是间歇运行。 在拟议的工作中，我们将考虑如何通过开发一种新的高效、稳定和耐热循环的SOEC来推动CO2利用SOEC的发展。传统的SOEC是由陶瓷材料制成的。镍具有良好的活性，通常用作阴极电催化剂；然而，二氧化碳使其容易沉积碳，从而阻碍电池的性能。前景看好的替代品，如钙钛矿，没有这个问题，但它们的活性仍然太低，无法奏效。金属支持的SOEC(MS-SOEC)结合了沉积在金属载体上的薄电极和电解液层，为全陶瓷电池提供了一种很好的替代方案。它们对热循环和氧化还原循环的高度耐受性使其非常适合间歇性可再生能源，但由于使用了镍，它们容易产生碳沉积。 这项拟议的工作旨在通过开发具有钙钛矿基阴极的MS-SOEC，实现对二氧化碳电解的高稳定性和高活性，将钙钛矿型耐焦性的优势与金属支撑电池更好的循环耐受性结合在一起。为了实现这一目标，我们将1)改变钙钛矿的组成和结构，以在阴极上开发更活跃和更稳定的材料；2)沉积电纺纳米纤维，以开发更活跃的阳极；3)设计一种程序，在MS-SOEC阴极渗透新的钙钛矿材料；以及4)结合所有步骤来制造完整的电池。这将包括实验、理论研究和高级模拟相结合，以准确预测碳沉积。

High levels of atmospheric CO2 are causing climate change, which creates more extreme weather patterns, among other problems. The transition to energy systems with no or low CO2 emissions must be expedited, but it will take time. As we move towards a renewable energy-based future, we must cope with the CO2 produced by our current fossil fuel-based energy paradigm. Proposed workarounds include carbon capture and storage (CCS) and carbon capture and utilization (CCU). In CCS, CO2 is captured and injected into geological formations. While CCS can sequester large amounts of CO2, it can be done only in limited locations. In CCU, captured CO2 is used to produce chemicals and fuels. Although CO2 can be used directly as feedstock, it is advantageous to first convert CO2 to carbon monoxide (CO) and then use the CO, usually with hydrogen (H2), to form new products. CO2 can be converted to CO through electrolysis, where electricity breaks CO2 in CO. Solid oxide electrolysis cells (SOECs) use electricity to convert CO2 and H2O into CO and H2. Provinces, like Ontario where electricity is generated with low CO2 emissions, are well-positioned to capitalize on this technology. Furthermore, SOECs can be well-suited for electricity that originates from renewable energy, which is characterized by intermittent operation. In the proposed work, we will consider how to advance the development of SOEC for CO2 utilization by developing a new effective, stable and thermal cycling tolerant SOEC. Conventional SOECs are made of ceramic materials. Nickel, which has excellent activity, is commonly used as a cathode electrocatalyst; however, CO2 makes it prone to carbon deposition which hinders the cell's performance. Promising alternatives, such as perovskites, do not have this problem, but their activity is still too low to be effective. Metal-supported SOECs (MS-SOEC), which incorporate thin electrodes and electrolyte layers deposited on a metal support, provide a good alternative to the all-ceramic cell. Their high tolerance to thermal and redox cycling makes them ideally suited for intermittent renewable energy sources, but they are prone to carbon deposition due to the Ni used. The proposed work aims to combine the benefits of perovskite's coking resistance and the metal-supported cell's better cycling tolerance through the development of a MS-SOEC with a perovskite-based cathode that will achieve high stability and activity toward CO2 electrolysis. To achieve this objective, we will 1) change the perovskite's composition and structure to develop more active and stable materials at the cathode; 2) deposit electrospun nanofibers to develop a more active anode; 3) devise a procedure to infiltrate the new cathode perovskite material at the MS-SOEC cathode; and 4) combine all steps to fabricate a complete cell. This will involve a combination of experiments, theoretical studies, and advanced simulation to accurately predict carbon deposition.