Yttria-Doped Ceria Surface Modification Layer via Atomic Layer Deposition for Low-Temperature Solid Oxide Fuel Cells

Abstract

Atomic layer deposition (ALD) is performed to obtain less than 1 nm thick yttria-doped ceria (YDC) layers as cathode functional layers to increase the surface oxygen incorporation rate for low-temperature solid oxide fuel cells (LT-SOFCs). Introducing a YDC surface modification layer (SML) has revealed that the optimized yttria concentration in YDC can catalyze surface oxygen exchange kinetics at the interface between the electrolyte and cathode. The YDC SML-containing fuel cell performs 1.5 times better than the pristine fuel cell; the result is an increased exchange current density at the modified surface. Moreover, a heavily doped YDC SML degrades the performance of LT-SOFCs, owing to the weakened oxygen surface kinetics due to the increased migration energy of the oxygen ions.

Recent Advances and Challenges in Thin-Film Fabrication Techniques for Low-Temperature Solid Oxide Fuel Cells

“…It was shown that, despite the lower deposition rate of ALD, the final quality obtained for the ALDdeposited layer was higher than the films deposited by sputtering, where a 30 times higher ionic conductivity was reported for ALD GDC [353]. Other ceria-doped composites such as yttria-doped ceria (YDC) have also been processed by ALD for SOFC application [354]. Balle et al studied the properties of ALD YDC while changing the Y content in a 10-20% range.…”