화학공학소재연구정보센터
Journal of Power Sources, Vol.274, 211-218, 2015
Impregnation of La0.4Ce0.6O1.8-La0.4Sr0.6TiO3 as solid oxide fuel cell anode in H2S-containing fuels
Active anodes were fabricated via wet chemical impregnation of optimized amount of La0.4Sr0.6TiO3 (L4ST) into La0.4Ce0.6O1.8 (LDC) pre-infiltrated porous yttria-stabilized zirconia (YSZ) matrix. Impregnations of 10 wt% LDC with 16 wt% L4ST significantly improved the performance of the fuel cell from 48 mW cm(-2) for pure L4ST to 161 mW cm(-2) for LDC-L4ST at 900 degrees C in H-2. The contribution of the preloaded LDC to this improvement was investigated using electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) as well as transmission electron microscopy (TEM). The measurement results indicated that pre-infiltrated LDC increased the activity of the anode more effectively by decreasing the total polarization resistance of the cell from 3.3 Omega cm(2) to 1.0 Omega cm(2) in humidified Hy at 900 degrees C. More importantly, the LDC nano-deposits (<20 nm) behaved as an effective "adhesive" that substantially enhanced the wettability of L4ST on YSZ matrix, resulting in finer and more uniform structure of L4ST infiltrates. The LDC L4ST cells also demonstrated significantly improved performances in 0.5% H2S-H-2 and 0.5% H2S- CH4 with higher stability than cells with pure L4ST anode. (C) 2014 Elsevier B.V. All rights reserved.