Characterization and performance of cobalt-free perovskite-type La0.6Ba0.4Fe0.8Ni0.2O3 − δ cathode material for intermediate-temperature solid oxide fuel cells

Abstract

A novel cobalt-free perovskite La 0.6 Ba 0.4 Fe 0.8 Ni 0.2 O 3 − δ (LBFN) powder was synthesized using a combustion method. The phase composition, electrical conductivity, thermal expansion coefficient (TEC), and electrochemical properties of LBFN were systematically investigated. The X-ray diffraction (XRD) results revealed that LBFN had a high chemical compatibility with Ce 0.8 Sm 0.2 O 2 − δ (SDC). The LBFN cathode exhibited a competitive electrode area-specific resistance (ASR) for the symmetric cell based on SDC electrolyte. Furthermore, the electrochemical performance of LBFN cathode could be effectively improved with the addition of the proper amount of SDC. Using the LBFN-SDC73 (7:3 in weight ratio) as a composite cathode, the Ni-SDC-supported single cell with a 25-μm-thick SDC electrolyte exhibited maximum power densities of 330, 216, and 119 mW cm −2 at 600, 550, and 500°C, respectively.

Novel cobalt and strontium-free perovskite Pr0.5Ba0.5Fe1-xNixO3-δ (x=0 and 0.2) as cathode for intermediate-temperature solid oxide fuel cells

“…It can be concluded that Pr 0.5 Ba 0.5 Fe 1-x Ni x O 3-δ (x = 0 and 0.2) oxides have the potential to be cathode materials for SOFCs. Moreover, all of them have relatively excellent electrochemical performance when Ni doping amount is 0.2 in the A-site alkaline earth metal-doped cobalt and strontium-free cathode materials, as reported in La 0.6 Ba 0.4 Fe 0.8 Ni 0.2 O 3-δ [28], La 0.6 Ca 0.4 Fe 0.8 Ni 0.2 O 3-δ [29], Pr 0.4 Ca 0.6 Fe 0.8 Ni 0.2 O 3 [30], and Pr 0.5 Ba 0.3 Ca 0.2 Fe 1-x Ni x O 3-δ [31]. Motivated by these findings, we prepared novel perovskite Pr 0.5 Ba 0.5 Fe 1-x Ni x O 3-δ (x = 0 and 0.2) as cathode electrocatalysts by a sol-gel method, study in detail its potential as a new type of perovskite cathode, and discuss the influence of Ni substitution on the structure and electrochemical properties of Pr 0.5 Ba 0.5 FeO 3-δ .…”

Role of Cu and Sr in Improving the Electrochemical Performance of Cobalt-Free Pr1-xSrxFe1-yCuyO3-δCathode for Intermediate Temperature Solid Oxide Fuel Cells

“…Cobalt-free cathodes for intermediate temperature solid oxide fuel cells (IT-SOFCs) have been the subject of a number of studies in recent years. 1,2 In addition to avoiding shortcomings suffered by cobaltcontaining cathodes, such as high cobalt cost, low long-term chemical stability and high thermal expansion coefficient (TEC), some cobalt-free cathodes show comparable or even better electronic conductivity and catalytic activity for oxygen reduction reactions (ORR) comparing with those cobalt counterparts. 3 Among the cobalt-free cathodes, copper-iron based perovskite oxides have attracted much attention for their low price and abundance of copper, excellent electro-catalytic activity for ORR as well as favorable thermal and chemical stability to withstand the cathode environment.…”