About this Abstract |
| Meeting |
MS&T26: Materials Science & Technology
|
| Symposium
|
Ceramics for Clean Hydrogen
|
| Presentation Title |
Engineered Oxide Heterointerfaces Enable Vacancy–Redox Coupling for Reversible Protonic Ceramic Cells |
| Author(s) |
Shuanglin Zheng, Hanping Ding |
| On-Site Speaker (Planned) |
Shuanglin Zheng |
| Abstract Scope |
Achieving efficient and durable oxygen electrocatalysis in protonic ceramic cells (PCCs) demands precise control of defect chemistry and cation redox under steam. Here we design a hierarchically engineered oxygen electrode comprising a three-dimensional, mesh-like PrNi0.7Co0.3O3−δ (PNC) scaffold conformally integrated with a vacancy-rich PrOx nanophase. This architecture extends the reactive zone, while the PrOx−PNC interphase enables vacancy-mediated redox coupling between Pr and Co, buffering the local oxygen chemical potential and stabilizing the defect landscape during reversible operation. The enhanced activity is attributed to vacancy-assisted steam activation and defect-mediated oxygen surface exchange, consistent with interfacial modulation of metal−oxygen covalency within an O 2p band-center framework. The electrode delivers 1.75 W cm−2 in fuel-cell mode and 2.77 A cm−2 at 1.3 V in electrolysis at 600°C, maintains >92% Faradaic efficiency, and shows minimal degradation over 200 h. Our results establish a strategy for coupling hierarchical transport with redox-buffered interphases in protonic electrochemical systems. |
