CAREER: Unraveling Oxygen Electrode Delamination Mechanisms in Reversible Solid Oxide Cells for Robust Hydrogen Production

Reversible solid oxide cells are devices that can switch between two opposite operating modes for hydrogen production and power generation. These devices can potentially revolutionize the way hydrogen is made. Despite the promise, though, use of these devices faces significant challenges due to fast degradation of the cell under prolonged operation. This Faculty Early Career Development (CAREER) award supports research aiming to understand the complex degradation mechanisms within reversible solid oxide cells. By overcoming these challenges, the technology can enable cost-effective use of hydrogen as a clean fuel in industries and the heavy-duty transportation sector. Utilizing hydrogen as a long-term energy storage solution, it also promotes the integration of renewable energy sources into the grid. This research spans multiple disciplines such as solid mechanics, electrochemistry, and advanced imaging. In alignment with UMass Lowell's mission as a Minority Serving Institution, the project seeks to encourage inclusivity by engaging underrepresented groups in energy engineering research and education, fostering a more diverse and inclusive workforce in the field. The rapid degradation in reversible solid oxide cells during electrolysis mode, caused by delamination failure at the oxygen electrode/electrolyte interface, is commonly associated with the buildup of oxygen partial pressure. Significant scientific challenges persist in fully comprehending the mechanisms responsible for the reduced degradation observed under reversible modes, especially with a bilayer oxygen electrode configuration. This research aims to bridge the existing knowledge gap by investigating the intricate interactions between mechanical and chemical stresses at the oxygen electrode-electrolyte interface under dynamic operating conditions, utilizing integrated mechano-electro-chemical approaches. The research will attempt to unravel the complex dynamics of crack initiation and propagation within 3D heterogeneous microstructures of oxygen electrodes from advanced full-field X-ray imaging technique. Through rigorous coupling of model and experiment approaches, the contributions of material variations and structural geometry modifications to performance improvements will be delineated. These findings will make a marked impact on the design of new oxygen electrodes and development of protocols for safe operation of reversible solid oxide cells. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.