Electrical Properties of La0.6Sr0.4Co1–yFeyO3 (y = 0.2–1.0) Fibers Obtained by Electrospinning

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• 作者：Marcieli Lubini ; Eva Chinarro ; Berta Moreno ; Vania C. de Sousa ; Annelise K. Alves ; Carlos P. Bergmann
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：January 14, 2016
• 年：2016
• 卷：120
• 期：1
• 页码：64-69
• 全文大小：341K
• ISSN：1932-7455

文摘

La_xSr_1–xCo_1–yFe_yO₃ (LSCF) is a promising material for intermediate temperature solid oxide fuel cell (IT-SOFC) cathodes. The fabrication of LSCF cathodes composed of fibers might enhance SOFC dispositive currents due to facilitating gas permeability through a porous structure. In the present work, La_0.6Sr_0.4Co_1–yFe_yO₃ (y = 0.2–1.0) fibers were obtained by electrospinning, and the structure and electrical properties were investigated. 1 μm wide LSCF fibers were obtained after the electrospun fibers were thermal treated at 1000 °C to remove the polymer and form the crystalline perovskite materials. The electrical conductivity of LSCF fibers as a function of temperature was measured using 2-point and 4-point probe methodologies for all compositions prepared, and the associate charge carrier activation energies were calculated using the Arrhenius model. The electrical conductivity increases with an increase in temperature from room temperature to 700 °C; this suggests a predominant small-polaron hopping mechanism. Above 700 °C, the LSCF fibers show a semiconductor-metal transition, and the electrical conductivity decreases.