Kim, Si-Won Bae, Yonggyun Yoon, Kyung Joong Lee, Jong-Ho Lee, Jong-Heun Hong, Jongsup 2024-01-19T23:30:55Z 2024-01-19T23:30:55Z 2021-09-03 2018-02-28 0378-7753 https://pubs.kist.re.kr/handle/201004/121689 To mitigate CO2 emissions, its reduction by high-temperature electrolysis using solid oxide cells is extensively investigated, for which excessive steam supply is assumed. However, such condition may degrade its feasibility due to massive energy required for generating hot steam, implying the needs for lowering steam demand. In this study, high-temperature electrolysis of CO2-enriched mixtures by using fuel-electrode supported La0.6Sr0.4CoO3/YSZ/Ni-YSZ solid oxide cells is considered to satisfy such needs. The effect of internal and external steam supply on its electrochemical performance and gas productivity is elucidated. It is shown that the steam produced in-situ inside the fuel-electrode by a reverse water gas shift reaction may decrease significantly the electrochemical resistance of dry CO2-fed operations, attributed to self-sustaining positive thermo-electrochemical reaction loop. This mechanism is conspicuous at low current density, whereas it is no longer effective at high current density in which total reactant concentrations for electrolysis is critical. To overcome such limitations, a small amount of external steam supply to the CO2-enriched feed stream may be needed, but this lowers the CO2 conversion and CO/H-2 selectivity. Based on these results, it is discussed that there can be minimum steam supply sufficient for guaranteeing both low electrochemical resistance and high gas productivity. English ELSEVIER SCIENCE BV CO-ELECTROLYSIS SYNGAS PRODUCTION COELECTROLYSIS CO2/H2O H2O High-temperature electrolysis of CO2-enriched mixtures by using fuel-electrode supported La0.6Sr0.4CoO3/YSZ/Ni-YSZ solid oxide cells Article 10.1016/j.jpowsour.2017.12.060 1 JOURNAL OF POWER SOURCES, v.378, pp.369 - 374 JOURNAL OF POWER SOURCES 378 369 374 scie scopus 000427316300042 2-s2.0-85039768987 Chemistry, Physical Electrochemistry Energy & Fuels Materials Science, Multidisciplinary Chemistry Electrochemistry Energy & Fuels Materials Science Article CO-ELECTROLYSIS SYNGAS PRODUCTION COELECTROLYSIS CO2/H2O H2O Electrolysis CO2 reduction Solid oxide cell Area specific resistance CO2 conversion Syngas selectivity