Praseodymium-doped ceria electrolyte powders are synthesized by a co-precipitation method using ammonium carbonate in little excess to fabricate a stable electrolyte-supported solid oxide fuel cell able to operate in hydrogen conditions. Raman and X-ray Photoelectron Spectroscopy are employed for the electrolyte characterization to check the distribution of vacancies and the initial oxidation state of Pr that influences the transport mechanism under the real operation of SOFCs. The optimum Pr concentration in the electrolyte is found to be 6 mol% of Pr and 14 mol% of Gd (sample 6Pr). The electrolyte-supported cells fabricated with this composition are sintered at 1250 °C for 3 h and tested in different gas conditions and operating temperatures, showing a maximum power density of 305.31 mW·cm-2 at 530.36 mA·cm-2 (750 °C) in wet hydrogen conditions. Compared to standard cells fabricated with a gadolinium-doped ceria electrolyte sintered at 1500 °C, the 6Pr has long term stability performances with a power density loss of 17% after 100 h of operation. The results demonstrate the eligible use of this electrolyte under real operating environments.
On the oxygen vacancies optimization through Pr co-doping of ceria-based electrolytes for electrolyte-supported solid oxide fuel cells
Dell'Agli G.;Spiridigliozzi L.;
2020-01-01
Abstract
Praseodymium-doped ceria electrolyte powders are synthesized by a co-precipitation method using ammonium carbonate in little excess to fabricate a stable electrolyte-supported solid oxide fuel cell able to operate in hydrogen conditions. Raman and X-ray Photoelectron Spectroscopy are employed for the electrolyte characterization to check the distribution of vacancies and the initial oxidation state of Pr that influences the transport mechanism under the real operation of SOFCs. The optimum Pr concentration in the electrolyte is found to be 6 mol% of Pr and 14 mol% of Gd (sample 6Pr). The electrolyte-supported cells fabricated with this composition are sintered at 1250 °C for 3 h and tested in different gas conditions and operating temperatures, showing a maximum power density of 305.31 mW·cm-2 at 530.36 mA·cm-2 (750 °C) in wet hydrogen conditions. Compared to standard cells fabricated with a gadolinium-doped ceria electrolyte sintered at 1500 °C, the 6Pr has long term stability performances with a power density loss of 17% after 100 h of operation. The results demonstrate the eligible use of this electrolyte under real operating environments.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
