Characterization of La1.96Sr0.04CuO4+d-Ce0.9Gd0.1O1.95 composite cathode for intermediate-temperature solid oxide fuel cell

Abstract

The performance ofLaI.96SrO.04Cu04+õ (LSC) - x CeO.9Gdo.lOI.95 (CGO) (x=0，10, 20, 30 wt%) composite cathodes has been investigated for their potential application in intermediate-temperature solid oxide fuel cells (IT-SOFCs). The individual structural phases of the composite cathodes were characterized using a third-generation synchrotron source beamline powder X-ray diffractometer XRD). Porous grain morphology of CGO-LSC cathode composite of the symmetrical half-cell was investigated from the cross-sectional scanning electron microscopy images and the elemental line profiles. The addition of CGO to LSC cathode further reduces the polarization resistance. The composite cathode of 20 wt%CGO-80 wt% LSC (CL20-80) coated on Ce0.9Gd0.1O1.95 electrolyte showed a lowest area specific resistance (ASR) i.e., 0.07 Ocm2 at 750 oC. An electrolyte supported (300 um thick) single-cell configuration of CL20-80/CGO/Ni-CGO attained a maximum power density of 626 mWcm-2 at 700 oC. The unique composite composition of CL20-80 demonstrates enhanced electrochemical performance and good chemical compatibility with CGO eletrolyte compared with their pristine LSC cathode for IT-SOFCs.