Enhanced methane steam reforming activity and electrochemical performance of Ni 0.9 Fe 0.1 -supported solid oxide fuel cells with infiltrated Ni-TiO 2 particles

Abstract

Ni 0.9 Fe 0.1 alloy-supported solid oxide fuel cells with NiTiO 3 (NTO) infiltrated into the cell support from 0 to 4 wt.% are prepared and investigated for CH 4 steam reforming activity and electrochemical performance. The infiltrated NiTiO 3 is reduced to TiO 2 -supported Ni particles in H 2 at 650 °C. The reforming activity of the Ni 0.9 Fe 0.1 -support is increased by the presence of the TiO 2 -supported Ni particles; 3 wt.% is the optimal value of the added NTO, corresponding to the highest reforming activity, resistance to carbon deposition and electrochemical performance of the cell. Fueled wet CH 4 at 100 mL min '1, the cell with 3 wt.% of NTO demonstrates a peak power density of 1.20 W cm '2 and a high limiting current density of 2.83 A cm '2 at 650 °C. It performs steadily for 96 h at 0.4 A cm '2 without the presence of deposited carbon in the Ni 0.9 Fe 0.1 -support and functional anode. Five polarization processes are identified by deconvoluting and data-fitting the electrochemical impedance spectra of the cells under the testing conditions; and the addition of TiO 2 -supported Ni particles into the Ni 0.9 Fe 0.1 -support reduces the polarization resistance of the processes ascribed to CH 4 steam reforming and gas diffusion in the Ni 0.9 Fe 0.1 -support and functional anode.