Ultrathin Atomic Layer-Deposited CeO2 Overlayer for High-Performance Fuel Cell Electrodes

• Published in: ACS applied materials & interfaces 2019-12, Vol.11 (50), p.46651-46657
• Main Authors: Shin, Jeong Woo, Oh, Seongkook, Lee, Sungje, Yu, Jin-Geun, Park, Joonsuk, Go, Dohyun, Yang, Byung Chan, Kim, Hyong June, An, Jihwan
• Format: Article
• Language: English
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.9b10572

Obtaining a catalyst with high activity and thermal stability is essential for high-performance energy conversion devices operating at an elevated temperature. Herein, the design and fabrication of a heterogeneous catalyst with an ultrathin CeO2 overlayer via atomic layer deposition (ALD) on Pt electrodes for low-temperature solid oxide fuel cells (LT-SOFCs) is reported. The cell with a CeO2-overcoated (five ALD cycles) Pt cathode shows lower activation resistance by 50% after a 10 h operation and higher thermal stability by a factor of 2 compared with the cell with a Pt-only cathode, which is known to be the best single catalyst at 450 °C. Eventually, a thin-film SOFC with a highly active and stable CeO2-overcoated cathode based on an anodized aluminum oxide (AAO) substrate demonstrates a high peak power density of 800 mW cm–2 at 500 °C, which is the highest performance ever reported for an AAO-based SOFC at this temperature.