Low-Cost Getters for Gaseous Chromium Removal in High-Temperature Electrochemical Systems
- 58 Downloads
Electrochemical performance degradation of the air electrode due to the presence of trace levels of gaseous chromium impurities, a critical issue in high-temperature electrochemical systems, contributes to long-term irreversible performance instabilities. We report a low-cost getter comprised of SrO and NiO to capture extrinsic chromium impurities present in ambient air. Ceramic honeycomb-supported getters have been tested for 500 h under SOFC cathode exposure conditions and characterized by scanning electron microscopy–energy dispersive X-ray spectrometry and focused ion beam–transmission electron microscopy. Chemical and structural analyses show that gaseous chromium predominantly concentrates within ~ 4–5 mm at the air inlet, leaving only the remainder of the getter free of chromium. Chromium capture mechanisms are proposed and discussed based on experimental findings and thermodynamic calculations.
The authors acknowledge the financial support from the US Department of Energy and National Energy Technological Laboratory under federal Grant DE-FE 0023385. Technical discussion with Dr. Patcharin Burke (NETL) is gratefully acknowledged. The authors also acknowledge Dr. Lichun Zhang and Ms. Chiying Liang for their help with SEM–EDS and FIB-TEM experiments.
- 6.P. Singh, S.L. Suib, M.B. Venkataraman, V. Manthina, M.K. Mahapatra, and U. Pasaogullari, High temperature electrochemical systems and related methods; US 2016/0072143 A1, 2014.Google Scholar
- 7.National Ambient Air Quality Standards (NAAQS) | Technology Transfer Network | US EPA. US EPA, OAR, Off. Air Qual. Plan. Stand.Google Scholar
- 12.A.N. Aphale, C. Liang, B. Hu, and P. Singh, Solid Oxide Fuel Cells Lifetime and Reliability: Critical Challenges Fuel Cells, ed. N. Brandon (Cambridge: Academic Press, 2017), p. 102.Google Scholar
- 16.E.H. Copland, D.L. Myers, E.J. Opila, and N.S. Jacobson, in 199th Electrochemical Society Meeting (Electrochemical Society, Inc., Washington, DC, 2001).Google Scholar