Evaluation of bismuth doped La2-xBixNiO4+δ (x=0, 0.02 and 0.04) as cathode materials for solid oxide fuel cells

Bismuth doped La2-xBixNiO4+delta (x = 0, 0.02 and 0.04) oxides are investigated as SOFC cathodes. The effects of Bi doping on the phase structure, thermal expansion, electrical conduction behavior as well as electrochemical performance are studied. All the samples exist as a tetragonal Ruddlesden-Popper structure. Bi-doped LBNO-0.02 and LBNO-0.04 have good chemical and thermal compatibility with LSGM electrolyte. The average TEC over 20-900 degrees C was 13.4 x 10(-6) and 14.2 x 10(-6) K-1 for LBNO-0.02 and LBNO-0.04, respectively. The electrical conductivity was decreasing with the rise of Bi doping content. EIS measurement indicates Bi doping can decrease the ASR values. At 750 degrees C, the obtained ASR for LBNO-0.04 is 0.18 Omega cm(2), which is 56% lower than that of the sample without Bi doping, suggesting Bi doping is beneficial to the electrochemical catalytic activity of LBNO cathodes.

Automated summary

The study investigated the performance of Bismuth doped La2-xBixNiO4+delta as SOFC cathodes, demonstrating improved thermal and electrical conductivity with Bi doping. Results suggest that Bi doping can enhance the electrochemical catalytic activity of the cathodes.