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

大气中高浓度的二氧化碳正在引起气候变化，造成更多的极端天气模式，以及其他问题。必须加快向零二氧化碳排放或低二氧化碳排放的能源系统过渡，但这需要时间。随着我们走向以可再生能源为基础的未来，我们必须应对目前以化石燃料为基础的能源模式所产生的二氧化碳。建议的解决方案包括碳捕获和储存（CCS）和碳捕获和利用（CCU）。在CCS技术中，二氧化碳被捕获并注入到地质构造中。虽然CCS可以隔离大量的二氧化碳，但它只能在有限的地方进行。在CCU中，捕获的二氧化碳用于生产化学品和燃料。虽然CO2可以直接用作原料，但首先将CO2转化为一氧化碳（CO），然后通常与氢气（H2）一起使用CO形成新产品是有利的。二氧化碳可以通过电解转化为CO，其中电力将CO中的二氧化碳分解。固体氧化物电解电池（SOECs）利用电力将二氧化碳和H2O转化为CO和H2。像安大略这样二氧化碳排放量低的省份，在利用这项技术方面处于有利地位。此外，soec可以非常适合来自可再生能源的电力，其特点是间歇性运行。在本文中，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来推进二氧化碳利用的SOEC的发展。传统的soec是由陶瓷材料制成的。镍具有优良的活性，常用作阴极电催化剂；然而，二氧化碳使其容易产生碳沉积，从而阻碍了电池的性能。有希望的替代品，如钙钛矿，没有这个问题，但它们的活性仍然太低，无法有效。金属支撑的soec （MS-SOEC）将薄电极和沉积在金属支架上的电解质层结合在一起，为全陶瓷电池提供了一个很好的替代方案。它们对热和氧化还原循环的高耐受性使它们非常适合间歇性可再生能源，但由于使用了Ni，它们容易产生碳沉积。提出的工作旨在通过开发具有钙钛矿基阴极的MS-SOEC，将钙钛矿的抗结焦性和金属支撑电池更好的循环耐受性结合起来，从而实现高稳定性和对二氧化碳电解的活性。为了实现这一目标，我们将1)改变钙钛矿的成分和结构，在阴极处开发更活跃和稳定的材料；2)沉积电纺纳米纤维，制备活性更高的阳极；3)设计一种在MS-SOEC阴极处渗透新型阴极钙钛矿材料的工艺；4)结合所有步骤来制造一个完整的细胞。这将包括实验、理论研究和先进的模拟相结合，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.