The dissolution of nickel oxide cathodes in the electrolyte is one of the major technical obstacles to the commercialization of molten carbonate fuel cells (MCFC). A novel alternative cathode material for MCFC was synthesized, which was made of nano-size Co3O4 coated on the surface of Ni powder using a polymeric precursor based on the Pechini method. X-Ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDAX), electron microprobe analysis (EPMA), and Raman spectrometry were employed in characterization of the novel alternative cathode materials. The Co-coated Ni cathode prepared by the tape-casting technique has a lower solubility in the molten carbonate than in the NiO cathode under CO 2 : O2 (67 : 33) atmosphere at 650°C. The reason is that the nano-size Co3O4-coated Ni powder can significantly retard the dissolution of NiO in molten carbonate due to the formation of the stable LiCO1-yNiyO2 phase on the surface of NiO in molten carbonate. During 300 h cell operation, the closed-circuit voltage (CCV) of unit cells using NiO and Co-coated Ni cathodes were found to be 0.80 V and 0.82 V, respectively, at a current density of 150 mA cm-2. The results show that the Co-coated Ni cathode used as an alternative cathode could resolve the problems in scale-up of the electrode and lengthen the lifetime of MCFC.
ASJC Scopus subject areas
- Materials Chemistry