INVESTIGADORES
MOGNI Liliana Veronica
artículos
Título:
Electrochemical Characterization of the n= 2 Ruddlesden-Popper Sr3FeMO6+ä (M = Fe, Co, Ni) by Electrochemical Impedance Spectroscopy
Autor/es:
L. MOGNI; F. PRADO; A. CANEIRO
Revista:
ECS Transactions
Editorial:
Electrochemical Society
Referencias:
Año: 2008 vol. 6 p. 233 - 243
ISSN:
1938-5862
Resumen:
The electrochemical characterization of the porous Sr3FeMO6+d(M= Fe, Co, Ni) electrode materials has been performed by a.c. electrochemical impedance spectroscopy (EIS) under pure O2 atmosphere and temperatures between 500 and 800 oC. Thick films of porous Sr3FeMO6+d were deposited on both sides of a dense Ce0.9Gd0.1O2-x electrolyte disc by spray deposition. To reach an adequate adherence between electrolyte and electrodes the cell was heat treated at 1000 oC during 1 h. XRD and SEM were used to evaluate the structure and microstructure of the cells before and after the EIS measurements. Data of the Area Specific Resistance (ASR), defined by ASR = Z(¥)-Z(0), associated with the overall oxygen reduction reaction, were obtained for the three compositions (Sr3Fe2O6+d, Sr3FeCoO6+d, Sr3FeNiO6+d). The ASR values are quite similar for the Sr3FeNiO6+d and Sr3FeCoO6+d compositions, and they are higher than those of Sr3Fe2O6*d. The activation energy (Ea) corresponding to the ASR for the Sr3FeNiO6+d material (Ea 1.3 eV) is higher than those of Sr3FeCoO6+dand Sr3Fe2O6+d, (Ea 0.9-1.0 eV).
