54
Study on the ORR Mechanism and CO2-Poisoning Resistance of La0.8Sr0.2MnO3-δ-coated Ba0.5Sr0.5Co0.8Fe0.2O3-δ Cathode for Intermediate Temperature Solid Oxide Fuel Cells

Monday, 24 July 2017
Grand Ballroom East (The Diplomat Beach Resort)
P. Qiu (Huazhong University of Science and Technology), J. Yang (Huazhong University of Science & Technology), L. Jia (Huazhong University of Science and Technology), Y. Gong, J. Pu (Huazhong University of Science & Technology), and J. Li (Huazhong University of Science and Technology)
The LSM-coated BSCF cathode with 3D core-shell architecture had been fabricated by the solution impregnation technology and presented the excellent CO2-poisoning resistance at the operating temperature. The LSM shell limited the combination of CO2 and BSCF, making that the 3D core-shell cathode present the great CO2-poisoning resistance. The three-electrode measurement was carried out to investigate the ORR mechanism. As the intervention of LSM shell, the LSM-coated BSCF presented the different ORR rate-determining step comparing with the BSCF cathode. The formation of lattice oxygen was the rate-determining step for the LSM-coated BSCF cathode, while molecular oxygen surface adsorption for the BSCF cathode. In addition, the electrochemical stability was promoted greatly with the protection of LSM shell. The LSM-coated BSCF cathode could get the stable state at about 11 h under cathodic current passage of 400 mAcm-2 at 650 °C, while it was about 70 h for the BSCF cathode. The excellent electrochemical performance and CO2-poisoning resistance made that the LSM-coated BSCF cathode appears to be a promising cathode for IT-SOFCs.