Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (09): 2065-2070.doi: 10.3866/PKU.WHXB201206272

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

Synthesis and Electrochemical Properties of La1.6Sr0.4Ni1-xCuxO4 as Cathode Materials for Intermediate Temperature Solid Oxide Fuel Cells

LI Qiang, ZHAO Hui, JIANG Rui, GUO Li-Fan   

  1. Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, P. R. China
  • Received:2012-05-21 Revised:2012-06-26 Published:2012-08-02
  • Contact: LI Qiang E-mail:hematite1211@yahoo.com.cn
  • Supported by:

    The project was supported by the Fund from Heilongjiang Educational Department, China (12521396).

Abstract:

Cathodic materials La1.6Sr0.4Ni1-xCuxO4 (x=0.2, 0.4, 0.6, 0.8), for an intermediate temperature solid oxide fuel cell (IT-SOFC), were prepared by a glycine-nitrate process and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM). Results showed that no reaction occurred between the La1.6Sr0.4Ni1-xCuxO4 electrode and the Ce0.9Gd0.1O1.95 (CGO) electrolyte at 1000 °C, and that the electrode formed good contact with the electrolyte after sintering at 1000 °C for 4 h. Electrochemical AC impedance spectroscopy measurements were used to study cathodic performance. The La1.6Sr0.4Ni0.4Cu0.6O4 cathode gave the lowest polarization resistance (Rp) of 0.35 Ω·cm2 at 750 ° C in air. Electrode properties of La1.6Sr0.4Ni1-xCuxO4 were studied under various temperatures and oxygen partial pressures. The two main oxygen reduction processes at the cathode are the oxygen ion transfer from the triple phase boundary to CGO electrolyte, and the charge transfer process. Charge transfer is the major rate limiting step for La1.6Sr0.4Ni1-xCuxO4 cathode. The La1.6Sr0.4Ni0.4Cu0.6O4 cathode exhibited the lowest overpotential, about 45 mV for a current density of 45 mA·cm-2 at 700 °C in air. This preliminary work showed that the present La1.6Sr0.4Ni1-xCuxO4 materials may be potential cathodes for use in IT-SOFCs.

Key words: Intermediate temperature solid oxide fuel cell, La1.6Sr0.4Ni1-xCuxO4 cathode material, Glycine-nitrate process, Electrochemical property, Oxygen reduction reaction

MSC2000: 

  • O646