Abstract |
A solid oxide fuel cell (SOFC) is a highly efficient device for converting chemical energy to electrical energy. In addition to the efforts to reduce the operating temperature of SOFCs to below 600 °C, research studies of the basic mechanism of CO2 poisoning on cathode materials are envisioned to improve the operation of dual-chamber SOFCs using ambient air. In this work, we comparatively studied the CO2 poisoning effect on two highly active perovskites SrSc(0.175)Nb(0.025)Co(0.8)O(3-δ) (SSNC) and Ba(0.5)Sr(0.5)Co(0.8)Fe(0.2)O(3-δ) (BSCF), using complementary characterization techniques, e.g., powder X-ray diffraction (XRD), Fourier transform-infrared (FT-IR) spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM), CO2-temperature-programmed desorption (CO2-TPD), and electrochemical impedance spectroscopy (EIS). The SSNC cathode shows better tolerance to CO2 as compared with BSCF, which is attributed to the absence of Ba, higher average metal- oxygen bond energy (ABE) of SSNC, and the higher acidity of Nb(5+) cations, whereas the oxygen vacancy concentration plays a less important role.
|
Authors | Yuan Zhang, Guangming Yang, Gao Chen, Ran Ran, Wei Zhou, Zongping Shao |
Journal | ACS applied materials & interfaces
(ACS Appl Mater Interfaces)
Vol. 8
Issue 5
Pg. 3003-11
(Feb 10 2016)
ISSN: 1944-8252 [Electronic] United States |
PMID | 26760218
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
|