Study of LnBaCo2O6-d (Ln = Pr, Nd, Sm and Gd) doubled perovskites as new cathode material for ITSOFC

E. CHAVEZ; M. MULLER; L. MOGNI; A. CANEIRO

Iguazu-Argentina

Simposio; : SLAFES XIX; 2008

Oxides with double perovskites structures of general composition LnBaCo2O6-d;LnBaCo2O6-d;(Ln = Pr, Nd, Sm and Gd) were synthesized by solid state reaction with the purpose to evaluatenew materials to be used as cathodes in intermediate temperature solid oxide fuel cell (ITSOFC).A preliminary study about electrochemical properties was performed by impedancespectroscopy between 500 and 800 C under atmosphere of pure O2. Symmetrical cells were obtained by spray deposition of LnBaCo2O6-d;(Ln = Pr, Nd, Sm and Gd) at both sides of a dense ceramic electrolyte. The impedance spectroscopy measurements as a function oftemperatures show a hysteresis loop which could be associated to a tetragonal/orthorhombicphase transition. The existence of this transition was corroborated by high temperature X-Raydiffraction and Differential Scanning Calorimetry measurements.C under atmosphere of pure O2. Symmetrical cells were obtained by spray deposition of LnBaCo2O6-d;(Ln = Pr, Nd, Sm and Gd) at both sides of a dense ceramic electrolyte. The impedance spectroscopy measurements as a function oftemperatures show a hysteresis loop which could be associated to a tetragonal/orthorhombicphase transition. The existence of this transition was corroborated by high temperature X-Raydiffraction and Differential Scanning Calorimetry measurements.LnBaCo2O6-d;(Ln = Pr, Nd, Sm and Gd) at both sides of a dense ceramic electrolyte. The impedance spectroscopy measurements as a function oftemperatures show a hysteresis loop which could be associated to a tetragonal/orthorhombicphase transition. The existence of this transition was corroborated by high temperature X-Raydiffraction and Differential Scanning Calorimetry measurements.