Investigation on Sr0.2Na0.8Nb1-xVxO3 (x=0.1, 0.2, 0.3) as new ceramic anode materials for low-temperature solid oxide fuel cells

摘要

Variants of SNNV (Sr0.2Na0.8Nb1-xVxO3, X = 0.1-03) ceramic oxides were synthesized via wet chemical method. SNNVs show high electronic conductivity of > 100 S/cm when reduced in hydrogen at a relatively low temperature of 650 degrees C. In particular, 30% V-doped SNNV exhibited the highest conductivity of 300 S/cm at 450 degrees C. In order to investigate the fuel cell performance, Gd0.1Ce0.9O2-delta (GDC) based electrolyte-supported fuel cells were prepared to study the anode characteristics. Sr0.2Na0.8Nb0.9V0.1O3 (SNNV10)-GDC composite was used as an anode and La0.6Sr0.4Co0.2Fe0.8O3-delta (LSCF)-GDC as a cathode. Both electrodes were porous and sintered at 1050 degrees C for 2 h in air. The anode side of the fuel cell was infiltrated with 10 wt% GDC/Ni-GDC precursor to activate the anode for fuel oxidation. I-V characteristics were determined in gas conditions such as dry/humidified hydrogen and methane at 650 degrees C. With the infiltration Ni-GDC, peak power density (PPD) of 280 mW/cm(2) and 220 mW/cm(2) in dry H-2 and CH4, respectively, were obtained at 650 degrees C, which is higher than GDC alone as infiltrate. The high resistances in the humidified conditions are attributed to the lower conductivity of SNNV10 in high P-O2 atmospheres. (C) 2017 Elsevier B.V. All rights reserved.